Prep the ramekins: Preheat the oven to 350°F (175°C). Grease 4 ramekins (about 8 oz / 225ml each) and place them on a baking tray.
Mix dry ingredients: In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
Cream butter & sugar: In a large bowl, beat butter and sugar until light and fluffy, about 2–3 minutes.
Add eggs: Add eggs one at a time, mixing well after each addition. Beat in oil and vanilla extract.
Combine: Add the dry ingredients and buttermilk in alternating additions, beginning and ending with the flour mixture. Mix just until combined and smooth. Do not overmix.
Fill & bake: Divide the batter evenly between the ramekins, filling each about ⅔–¾ full. Bake for 25–30 minutes, or until the cakes are lightly golden and a toothpick inserted into the center comes out clean.
Cool: Allow the cakes to cool completely in the ramekins.
Level the cakes (optional): If the cakes domed while baking, run a knife around the edges and carefully remove them from the ramekins. Trim the tops slightly to create a flatter surface, then return them to the ramekins. This step is optional but gives a cleaner final look.
Make the Frosting: In a medium bowl, beat the butter and powdered sugar until light and creamy. Add the cream cheese and vanilla extract and beat until smooth and fluffy. If needed, add heavy cream, 2 tablespoons at a time, until the frosting reaches your desired consistency.
Decorate: Pipe or spread the frosting generously over each cake. Smooth the tops, then cover generously with sprinkles, pressing lightly so they stick well and fully coat the frosting.
Chill: Refrigerate for at least 1–2 hours before serving for the best texture and cleaner slices.
Sprinkles: For the classic viral Dot Cakes look, use rainbow sprinkles (also known as hundreds and thousands). Their tiny round shape creates the signature colorful coating and crunchy texture that makes these cakes so fun and unique.
Buttermilk substitute: No buttermilk? Mix ½ cup milk with 1½ teaspoons lemon juice or vinegar. Let sit for 5 minutes before using.
Heavy Cream: The heavy cream is optional and helps create a lighter, fluffier frosting with a softer texture. Skip it for a thicker and more stable frosting.
Frosting: For the smoothest frosting, make sure the butter and cream cheese are fully softened but not melted. If the frosting feels too soft:
Chill it for 30-60 minutes before frosting.
Or add a little more powdered sugar.
Storage: Store covered in the refrigerator for up to 4 days.