Preheat oven to 350°F (175°C). Line a 12-cup muffin tin with liners.
Cream Butter & Sugars
In a mixer bowl, beat butter, brown sugar, and granulated sugar until light and fluffy (2–3 minutes).
Add Wet Ingredients
Beat in eggs one at a time, then vanilla extract and cooled coffee. Scrape down sides.
Mix Dry Ingredients
Sift together flour, espresso powder, baking powder, and salt. Add on low speed until just combined.
Bake
Fill liners ½–⅔ full. Bake 14–16 minutes, until tops spring back. Cool completely on a wire rack.
Make Frosting
In a clean bowl, beat butter, half the powdered sugar, espresso powder, and salt on low. Gradually add remaining sugar and 2 tablespoons coffee; beat until smooth and fluffy. Add extra coffee if needed.
Decorate
Pipe buttercream onto each cooled cupcake. Top each with a single coffee bean.
Store
Store in an airtight container in the fridge up to 3 days. Bring to room temperature before serving.
Notes
Tips & Variations
Mocha Twist: Add ¼ cup unsweetened cocoa powder to the dry mix.
Espresso Muffins: Bake without liners for bakery-style tops.
Gluten-Free: Substitute a 1:1 gluten-free flour blend.
Make-Ahead: Freeze baked cupcakes; frost after thawing.