1-First Step: Prep Your Oven and Dry Ingredients Preheat your oven to 350°F (175°C). Line a muffin pan with 12 cupcake liners. In a large bowl, whisk 1 cup sugar with the zest of 1 lemon until it smells amazing and turns yellow. This releases those oils for max flavor. Add 1 1/4 cups flour, 1 1/2 tsp baking powder, and 1/2 tsp salt. Whisk well and set aside. Pro tip: Zest your lemon fresh for the best punch.

2-Second Step: Mix Wet Ingredients In another bowl, whisk 1/2 cup room-temp sour cream, 1/2 cup water, 1/4 cup oil, 1 egg, and 1 tsp vanilla. Stir until smooth. Want a fun yellow tint? Add a drop of yellow gel food coloring. Room-temp ingredients mix better and prevent lumps. Pour the dry mix into the wet. Whisk gently until just combined. No overmixing here!

3-Third Step: Fill and Bake Cupcakes Use a cookie scoop to fill liners 3/4 full. Even scoops mean uniform cupcakes. Bake 19-21 minutes. Toothpick test: a few moist crumbs means done. Cool 10 minutes in the pan, then transfer to a rack. Let them cool fully before filling. This step takes about 30 minutes total cooling time.

4-Fourth Step: Make Strawberry Buttercream Beat 1 cup room-temp butter on medium for 30 seconds until creamy. Add zest of 1 lemon, 1 tsp vanilla, 1 tsp lemon extract, and 1/4 tsp salt. Beat on low. Mix in 3 Tbsp seedless strawberry jam. Gradually add 3 1/2 cups powdered sugar and 1 Tbsp cream on low, scraping sides. For pink color, drop in red gel food coloring. If too thick, add cream 1 tsp at a time. Too thin? Powdered sugar 1/4 cup at a time. Broken? 1 Tbsp butter. Finish by hand stirring with a spatula for silky texture.

5-Fifth Step: Optional Marbled Piping Bag Spread 1 Tbsp strawberry jam thinly inside a piping bag. Cut the tip, fit a large round piping tip, add buttercream, and seal. This creates pretty swirls without extra work.

6-Sixth Step: Fill and Decorate Core cooled cupcakes with a knife or 3/4-inch cutter. Fill each with 1 Tbsp strawberry jam. Pipe tall swirls of buttercream. Garnish with thin lemon slices and heart-shaped strawberry pieces from 6 small berries. Slice strawberries lengthwise, cut a V notch for hearts. Now they’re party-ready!