I've mentioned before how roasting vegetables really brings out their flavor; it also softens their texture and nicely crisps or caramelizes the outside. 
For this dish, I placed one yellow bell pepper (cut into strips), 1/2 of a sliced Vidalia onion and 2 garlic cloves (left whole in their skins) on a baking sheet lined with aluminum foil and lightly sprayed with olive oil. I gave the vegs another quick spray and sprinkled them with some seasoning salt. (Tip: get a Misto olive oil sprayer - no need to buy cooking spray anymore!). I baked them at 425 for about 15 min, turning once. Then I added some grape tomatoes to the pan and baked the mixture for another 5 min or so. At this point I removed the pepper, placed it in a zip-lock bag, and sealed it, and transferred the onion and garlic to a plate to cool. I then added about a 1/2 pound of shrimp to the pan with the tomatoes and squeezed a little lemon over them, added another spray of olive oil and a few shakes of lemon pepper. After baking for about another 5 min, I took the pan out of the oven and folded the aluminum over the tomatoes and shrimp to keep warm. I peeled the papery covering off the garlic and put it in the work bowl of my food processor with the onion. I then took the pepper out of the baggie, gently removed the charred skins and added it to food processor with about 1/4 cup pitted olives, aout 1/4 tsp of crushed red pepper, a few sprigs each of basil and lemon balm, and a drizzle of olive oil. I pulsed all this together just a few times so it stayed chunky. I added this to the shrimp mixture and gently tossed it with some cooked spaghetti and garnished with a few basil leaves. Yum!