Preheat oven to 350 degrees. Place bread slices onto a cookie sheet and drizzle with olive oil and sprinkle with salt and pepper. Toast in the oven for about 8-10 minutes or until the edges begin to lightly brown.
Place the peach slices on a grill pan (or on a grill) about 1-2 minutes on each side or until grill marks appear.
Let the crostini cool slightly before placing about a spoonful of ricotta cheese on each.
Roll or fold the prosciutto to the size of your crostini and place on top of the ricotta. Top with peaches.