Heat the broth in a pot over medium heat. Once boiling, add the peas and cook until tender, about 5 minutes.
Drain the peas in a fine mesh sieve, reserving a tablespoon of the cooking liquid. Place the peas in a mini chopper or food processor. Add a few mint leaves and salt. Puree until smooth. If you need to, add a little bit of cooking liquid, just enough to make the puree smooth.
Toast the baguette slices in the oven for about 10 minutes at 400 degrees F, or in the air fryer for 3-4 minutes. Drizzle the crostini with olive oil.
Top each crostini with pea puree. Top each with a small roll of prosciutto, a mint leaf, and red pepper flakes.