Preheat oven to 400˚F (200˚C). Stir 3 tbsp (45 mL) oil with garlic, herbes de Provence, 1/2 tsp (2 mL) each salt and pepper. Rub on outside and inside fish. Set aside.
On work surface, arrange 3 slices prosciutto side by side, slightly overlapping. Place fish in center of prosciutto and wrap slices around fish. Place fish on parchment paper-lined baking sheet, with prosciutto seam-side down. Set aside.
Toss grape tomatoes with remaining oil, salt and pepper. Scatter on lined baking sheet around fish.
Bake 20 to 25 min. until fish is cooked through and beginning to flake, tomato skins are blistered, and prosciutto is crispy. Let stand 5 min. before serving.
For a flavour switch, substitute Italian seasoning for herbes de Provence.