Part 1: Ultra-Moist Cupcakes
Step 1 – Prepare oven & pans: Preheat to 175°C (350°F). Line two or three 12-cup muffin pans with liners (makes about 24–30 cupcakes).
Step 2 – Dry ingredients: Sift together self-rising flour, cinnamon, nutmeg, cloves, allspice, and baking soda. Set aside.
Step 3 – Wet ingredients: Beat sugar, oil, and vanilla on medium until combined. Add eggs one at a time, mixing well after each, until smooth and slightly lightened.
Step 4 – Finish batter: On low, add dry ingredients in a few additions just until combined. Fold in grated carrots, partially drained crushed pineapple, and walnuts (if using). Do not overmix.
Step 5 – Bake: Fill liners about 3/4 full (use a scoop for uniformity). Bake 15–20 minutes until a toothpick comes out clean. Cool a few minutes in pan, then transfer to a wire rack to cool completely before frosting.
Part 2: Brown Butter Cream Cheese Frosting
Step 6 – Brown the butter: Melt butter in a light-colored saucepan over medium heat. Cook, swirling, until brown bits form and it turns amber with a nutty aroma. Immediately transfer to a heatproof bowl to stop cooking.
Step 7 – Chill: Refrigerate until butter is completely solid (about 1 hour). You can speed this up in the freezer; watch closely.
Step 8 – Whip frosting: Beat chilled brown butter and cream cheese on high until smooth and fluffy. On low, add confectioners' sugar 1 cup at a time. Add salt and vanilla, then whip on high 2–3 minutes until light and airy.
Step 9 – Frost: Pipe generous swirls onto fully cooled cupcakes (large star tip is classic). Garnish with a drizzle of caramel and toasted nuts if desired.