Preheat oven to 400˚F. Grease a rimmed baking sheet with cooking spray.

Spread cherry tomatoes in an even layer on baking sheet. Roast until tomatoes burst, about 10 minutes, shaking the pan halfway through.

Reduce temperature to 375˚F.

Slice croissants in half lengthwise. Spread the bottom with mustard. Top the bottom with a slice of cheese, then a slice of prosciutto. Top each with some burst tomatoes and spread the top half of the croissant with fig jam.

Place the sandwiches on a baking sheet and bake for 6 minutes until warmed through and cheese is melted.