1. Preheat oven to 350F.
2. Slice loaf of bread into 1/2" rounds and place on a baking sheet. Toast until desired.
2. Remove bread from oven and let cool. Generously spread mascarpone on toasted bread.
3. Layer mascarpone with a slice of prosciutto.
4. Layer your choice of peach preserves or peach slices on prosciutto and serve.