Blend the peaches, adding sugar if desired, with water into a smooth purée.

Strain the peach purée. You should have about 3 cups of peach purée.

To prepare the peach bellini, pour the peach purée into champagne flutes or tall glasses and gently top off with prosecco. The ratio is about 1:1 or 1:1.5 peach purée to prosecco. Garnish with fresh raspberries if desired.

For a frozen peach bellini, mix the purée, champagne, and ice in a blender.

For a non-alcoholic peach bellini, replace the prosecco with chilled sparkling lemonade or sparkling white grape juice.