Step 1

Heat oven to 350°F (175°C).  Line 18 cupcake wells with cupcake liner; set aside.

Step 2

In a large bowl, whisk together flour, sugar, baking powder, salt. Set aside.

Step 3

In a separate large bowl using an electric mixer on medium speed, mix buttermilk, oil, lemon juice, eggs and zest until liquid becomes a homogenous blend, about 1 minute.

Step 4

Slowly pour liquid mixture in with the flour mixture and mix until just combined. Avoid overmixing. Pour about 1/4 cup of batter into each cupcake liner; about 3/4 full.

Step 5

Bake for 20 minutes, rotating pans about halfway through baking.  Cupcakes are ready when a wooden toothpick inserted in center comes out dry with just a few crumbs.  Allow cupcakes to cool on a wire rack to room temperature before frosting.

Step 6

Meanwhile, in a large chilled bowl using an electric mixer, beat heavy cream, powdered sugar and lemon juice until soft peaks begin to form.  Add in mascarpone cheese and continue to mix until stiff peaks form.

Step 7

In a piping bag fitted with a 1M star tip, fill bag with frosting and pipe in a circular motion beginning from the edge and working upwards toward the center. As you approach the tip, begin to release pressure and pull straight upward to form a tip. Sprinkle with lemon zest.  ENJOY!