Line a baking tray with aluminum foil and preheat the oven at 400 deg F. Add the tomatoes, salt, and pepper. Place the garlic heads in the tray as well. (I did not trim the ends and placed it as is)
Add the olive oil and combine them all. Ensure you have coated the tomatoes evenly with oil.
Now bake the tomatoes at 400 deg F for 50 minutes or until the tomatoes are blistered. After 50 minutes, let it sit in the oven for 10 minutes, then remove it from the oven. Let the tomatoes and garlic cool. Take the garlic heads and gently squeeze out the garlic cloves and discard the skins.
Store the roasted tomatoes along with garlic in air-tight containers or mason jar. (You can save the olive oil separately for pasta and salads or save it along with the tomatoes). Refer to the post for storing suggestions.
Adjust the salt and pepper to your taste.
Instead of grape tomatoes, you can use cherry tomatoes or regular tomatoes. Depending upon the size of the tomatoes, chop them into bite-sized pieces.
You can also include some herbs like thyme or rosemary or oregano, or basil for enhanced flavor.
After roasting for 50 minutes, you can increase the temperature to 450 deg F and roast again for 10 minutes. It brings out the sweetness of the tomatoes further.