Preheat the oven to 350° F and line 3 - 8 inch round cake pans with parchment paper and spray with nonstick cooking spray.
In the bowl of a stand mixer using the whisk attachment, add eggs and beat on high for 5 minutes until thickened and light. Lower speed to medium and slowly add sugar while beating an additional 5 minutes. Add flour, baking powder, and salt and beat to combine.
Pour in milk, melted butter, and almond extract and mix until just incorporated.
Divide mixture evenly into prepared baking pans and bake at 350° F for 25-30 minutes or until toothpick inserted in center comes out clean.
Cool cake, in pan, on wire baking rack for 30 minutes. Poke cake with the end of a meat fork or wooden spoon handle and slowly pour prosecco over cake.
Wrap tops of pans in plastic and place in fridge for 2-4 hours for prosecco to soak into the cake.
While the cake is baking, you can make the filling.
In a large bowl, combine peach chunks, sugar, and prosecco and stir to combine. Cover and let stand while baking and chilling cake.
Stir occasionally and mash with fork or potato masher while standing.
In the bowl of a stand mixer, add heavy cream, powdered sugar, and vanilla. Beat on high for 5 minutes or until stiff peaks form.
Place one layer of cake on plate or cake stand. Layer with half of the peach mixture. Top with second layer of cake and rest of peach mixture. Top with third layer of cake.
Spread top and sides of cake with frosting and garnish with additional peach slices, if desired.