• Heat oven to 350 F.
• Grease a 9x13 jelly-roll pan with cooking spray and line with parchment paper

For the Sponge:

• In a large bowl, beat eggs until fluffy, about 5 minutes. 
• In a separate bowl, sift flour, baking powder, and salt.
• While the mixer is running, slowly add sugar and mix for 3 minutes
• Add vegetable oil, buttermilk, and vanilla to the whipped eggs until just combined
• Gently fold in half of the dry ingredients until little or no flour is present, Fold in remaining flour to keep batter fluffy
• Pour batter into prepared pan and use an offset spatula to distribute batter evenly
• Bake for 12-15 minutes or until springs back when lightly pressed and has a golden color
• While the cake is baking, sprinkle a clean tea towel with powdered sugar, gently rubbing the sugar into the towel
• When the cake is done, turn it out quickly onto the prepared tea towel
• Peel off the parchment paper and immediately roll the cake up in the towel. Roll as tightly as possibly and evenly as possible
• Cool-wrapped cake on a wire rack for 15-30 minutes

For the Jelly Filling

• Add 2 cups of berries of your choice, 1 cup of sugar, and ¼ cup of fresh lemon juice.

  Add two fresh rosemary sprigs (optional) and a pinch of sea salt to a medium saucepan and cook over medium-high heat until the mixture thickens, about 15 minutes. Remove rosemary and discard. 
• Allow the mixture too cool for 5 minutes. Transfer the mixture to a small blender pulse mixture until smooth

For the Filling and Buttercream Frosting:

• In a large bowl of a stand mixer, whip mascarpone cheese, heavy cream, and vanilla to stiff peaks. Add powdered sugar and 2 tablespoons of cooled jelly and continue to mix for 30 seconds to combine

To Build the Swiss Roll:

• Gently unroll the cooled cake, do not remove from the towel
• Spread jelly evenly over the inside of the cake
• Using a large spoon, place dollops of whipped cream over the jelly then evenly spread the filling over the inside of the cake all the way to the edges.
• Roll the cake using the tea towel. Lift the jelly roll to a serving plate using the towel before removing it. Frost the cake with the remaining whipped cream and decorate with fresh berries and mint