Grandma’s Famous Sweet Potato Butter Cake Recipe for 12 Perfect Slices

There’s nothing quite like the smell of Grandma’s Famous Sweet Potato Butter Cake wafting through the kitchen. That rich, buttery aroma mixed with warm cinnamon and nutmeg instantly takes me back to her tiny farmhouse kitchen, where she’d let me lick the batter spoon while scolding me with a wink, “Just don’t tell your mother!” What makes this cake so special isn’t just the perfect balance of flavors – it’s how the sweet potatoes create this unbelievable moist crumb that stays tender for days. Grandma swore by her “old-school” methods: hand-mashing the sweet potatoes (never canned!), creaming the butter and sugar until it looked like spun gold, and that magical touch of buttermilk that makes every bite melt in your mouth. After years of perfecting her recipe, I can honestly say this cake tastes like love baked into every slice.

Why You’ll Love Grandma’s Famous Sweet Potato Butter Cake

Oh, where do I even start? This cake isn’t just dessert—it’s a hug in cake form. Here’s why you’ll fall head over heels for it:

• That melt-in-your-mouth texture: Thanks to the sweet potatoes and buttermilk, every bite stays moist for days (if it lasts that long!).
• The perfect balance of flavors: Warm spices dance with rich butter and sweet potatoes—it’s cozy and luxurious all at once.
• Foolproof baking: No fancy techniques here—just good old-fashioned mixing and baking. Even my cousin Dave (who burns toast) nailed it.
• Always a crowd-pleaser: From holiday dinners to “just because” Tuesdays, this cake turns any day into a celebration.

Trust me, one slice and you’ll understand why this recipe’s been passed down in our family for generations.

Ingredients for Grandma’s Famous Sweet Potato Butter Cake

Listen closely – these aren’t just ingredients, they’re the building blocks of magic! Grandma was very particular about each one, and after decades of baking this cake, I understand why. Here’s what you’ll need:

• 2 cups mashed sweet potatoes – and I mean freshly cooked and mashed, none of that canned stuff! Bake or boil them until fork-tender, then mash while warm. Pro tip: measure after mashing, not before.
• 1 cup unsalted butter, softened – leave it out for 1-2 hours until it gives when you press it. Grandma would say “as soft as a baby’s cheek.”
• 2 cups granulated sugar – plain white sugar works fine, though Grandma sometimes swapped 1/4 cup for brown sugar for extra depth.
• 4 large eggs – room temperature, please! Cold eggs make the butter seize up.
• 1 tsp vanilla extract – the real stuff, not imitation. It matters more than you think!
• 3 cups all-purpose flour – spoon and level it, don’t scoop straight from the bag!
• 1 tsp baking powder + 1/2 tsp baking soda – our rising dream team.
• 1/2 tsp salt – just enough to make all the flavors pop.
• 1 tsp cinnamon + 1/2 tsp nutmeg – the warm spice hug that makes this cake sing.
• 1 cup buttermilk – if you don’t have any, see my emergency buttermilk hack in the tips section!

See those notes? That’s 60 years of baking wisdom right there. Follow them, and you’re golden!

How to Make Grandma’s Famous Sweet Potato Butter Cake

Alright, let’s get baking! This is where the magic happens – turning simple ingredients into that unforgettable sweet potato butter cake. Follow these steps exactly like Grandma taught me, and you’ll have everyone begging for seconds.

Preparing the Batter

First things first – grab your biggest mixing bowl and that trusty wooden spoon (or stand mixer if you’re feeling fancy). Cream the softened butter and sugar together until it’s light, fluffy, and pale yellow – about 3-4 minutes. This step is crucial – it creates those tiny air pockets that make the cake tender. Add eggs one at a time, mixing well after each, then stir in the vanilla. The batter should look like sunshine!

Now for the dry team: whisk together flour, baking powder, baking soda, salt, and spices in another bowl. Alternate adding this with the buttermilk to the butter mixture, starting and ending with dry ingredients. Mix just until combined – overmixing makes tough cake! Finally, gently fold in those gorgeous mashed sweet potatoes until you’ve got a thick, orange-speckled batter that smells like heaven.

Baking and Cooling

Pour that beautiful batter into your prepared 9×13 pan (I like to give it a little shake to even it out). Slide it into the preheated 350°F oven and set your timer for 45 minutes. Around the 40-minute mark, start watching for that perfect golden-brown top. The real test? A toothpick inserted in the center should come out with just a few moist crumbs – no wet batter!

Here’s Grandma’s golden rule: let the cake cool in the pan for exactly 10 minutes before transferring to a wire rack. This lets it set without drying out. Resist cutting into it right away (I know, it’s hard!) – letting it cool completely makes for cleaner slices. Though if you ask me, a slightly warm piece with a dollop of whipped cream is absolute perfection.

Tips for the Perfect Grandma’s Famous Sweet Potato Butter Cake

After burning through countless batches (and learning from Grandma’s gentle scolding), here are my can’t-live-without tips for cake success:

• Sweet potato secrets: Bake (don’t boil!) your sweet potatoes – it concentrates their flavor. Let them cool slightly before mashing to avoid gummy texture.
• Buttermilk hack: No buttermilk? Mix 1 cup milk with 1 tablespoon lemon juice or vinegar, let it sit for 5 minutes until it curdles. Works like magic!
• Room temp is key: Cold ingredients don’t play nice. Take eggs and buttermilk out 1 hour before baking.
• Storage smarts: Keep leftovers covered at room temp for 3 days, or freeze slices wrapped in parchment for 2 months. Thaw overnight – tastes just-baked!

One last thing – always lick the bowl. Grandma said it’s the baker’s privilege!

Ingredient Substitutions for Grandma’s Famous Sweet Potato Butter Cake

Look, I get it – sometimes you’re halfway through the recipe and realize you’re out of something. Don’t panic! While Grandma would prefer you stick to the original, here are her approved swaps that still deliver amazing results:

• No buttermilk? The milk + lemon juice trick works (1 cup milk + 1 tbsp lemon juice), or use plain yogurt thinned with a splash of milk.
• Out of fresh sweet potatoes? Canned puree can work in a pinch – just drain it well and reduce any added liquid in the recipe.
• Spice variations: All out of nutmeg? Try a pinch of allspice or cloves instead. For cinnamon lovers, bump it up to 1 1/2 tsp!
• Butter emergency: In absolute desperation, you can use high-quality margarine, but expect slightly less rich flavor.

Remember – substitutions change the cake’s personality a bit, but the soul remains the same. As Grandma used to say, “The best cake is the one you share!”

Serving Suggestions for Grandma’s Famous Sweet Potato Butter Cake

Oh honey, this cake shines all on its own, but a little extra love never hurts! My family’s favorite way? Warm slices with a scoop of vanilla ice cream slowly melting over the top – pure bliss! For breakfast (don’t judge!), try it with a dollop of whipped cream and a drizzle of caramel. Coffee lovers, listen up – this cake pairs perfectly with a strong cup of black coffee to balance the sweetness. Holiday tip: dust with powdered sugar and cinnamon for a festive touch that’ll have everyone reaching for seconds!

Storage and Reheating Instructions

Listen up, because Grandma taught me the secret to keeping this cake tasting fresh for days! Store leftovers covered at room temperature for up to 3 days – the sweet potatoes keep it moist. For longer storage, wrap individual slices in parchment for up to 2 months. To reheat, pop a slice in the microwave for 15-20 seconds or warm it gently in a 300°F oven for 5 minutes. Pro tip: don’t refrigerate – it dries out the crumb faster than you can say “pass me another slice!”

Nutritional Information for Grandma’s Famous Sweet Potato Butter Cake

Now, let’s be real – this is dessert, not health food! But since you asked, here’s the scoop per generous slice (based on 12 servings): about 320 calories, 12g fat (7g saturated), 48g carbs (2g fiber, 20g sugar), and 5g protein. But listen – these numbers might dance around a bit depending on your exact ingredients. The sweet potatoes do pack vitamin A, so hey – that’s something, right? Just enjoy every bite and worry about numbers tomorrow!

Frequently Asked Questions

After years of baking this cake and fielding questions from friends, here are the answers to the things everyone wants to know:

Can I use canned sweet potatoes instead of fresh?
Grandma would frown, but yes – in a pinch! Just drain them really well and pat dry with paper towels. The texture will be slightly different, but still delicious.

How do I know when the cake is done baking?
Three signs never fail: the edges pull away from the pan, the top springs back when lightly touched, and a toothpick comes out with just a few moist crumbs (no wet batter!).

Can I make this into cupcakes?
Absolutely! Fill lined cupcake tins 2/3 full and bake at 350°F for 18-22 minutes. Makes about 24 perfect little cakes – great for sharing!

Why did my cake sink in the middle?
Usually means you opened the oven door too early (wait at least 30 minutes!) or your baking powder/soda might be old. Test them by mixing with vinegar – if they don’t bubble, time for new ones!

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