Strawberry Swiss Roll (Brazo de Reina)

• For the sponge cake:
• 6 large eggs, separated
• 6 tablespoons all-purpose flour , or Cup4Cup brand GF flour
• 6 tablespoons Monk Fruit sweetener, or sugar
• 2 teaspoons vanilla extract
• 2 teaspoons unsalted butter, at room temperature
• 1/4 cup powdered sugar, to sprinkle on towel and cake

For the filling:

• 1 pound strawberries, cut into thin slices
• 1 cup heavy cream
• 2 teaspoons vanilla
• 5 tablespoons Monk Fruit sweetener, or sugar
• 6 tablespoons 0% Greek yogurt
• powdered sugar, optional for serving