01 - Preheat oven to 350°F. Line a 9x13-inch baking sheet with parchment paper and lightly grease with butter or cooking spray.
02 - In a large mixing bowl, whisk together flour, granulated sugar, salt, and baking powder until thoroughly blended.
03 - In a separate bowl, beat eggs, milk, melted butter, and vanilla extract until smooth and well combined.
04 - Pour the wet mixture into the dry ingredients. Fold gently with a spatula until just combined, taking care not to overmix.
05 - Spread batter evenly onto the prepared baking sheet. Bake for 12 to 15 minutes until the cake springs back when lightly touched. Cool completely on a wire rack.
06 - While cake cools, whip heavy cream with powdered sugar and vanilla extract using an electric mixer until stiff peaks form.
07 - Carefully remove cooled cake from the pan onto a clean work surface. Trim the edges with a sharp knife for neat, even rolling.
08 - Spread whipped cream evenly over the entire cake surface, leaving a 1/2-inch border along one long edge. Sprinkle diced strawberries uniformly across the cream layer.
09 - Starting from the long edge opposite the border, tightly roll the cake using the parchment paper to guide and support the roll. Transfer to the refrigerator and chill for 20 minutes to set.
10 - Remove from refrigerator and slice the roll crosswise into 8 equal pieces, each approximately 1.5 inches thick.
11 - Arrange sushi pieces on a serving platter. Top each piece with a thin strawberry slice and sprinkle with chopped mint if desired. Serve chilled.