Place the peaches, lemon juice and sugar in a blender or food processor, and blend until the purée is completely smooth.

Press the mixture through a sieve and discard the peach solids in the sieve.

Place 2 tablespoons of the peach puree into each Champagne glass and fill with cold prosecco.

Gently stir with a spoon to combine.

Top off the drink with another splash of Prosecco and garnish with a peach slice, if desired.

Serve immediately. Cheers