Chop a large yellow onion into 1 inch chunks. Try not to cry. Set them aside.
Heat the olive oil in an ovenproof skillet (I use a 12-inch cast-iron) and add the onion to the skillet. Cook them down until the onions begin to caramelize and smell fragrant.
Add the garlic and cook for about 1 minute. Add the tomato paste and fry lightly, about 30 seconds. Be careful not to burn anything!
Add the chickpeas, marinara, and a little water. Season with salt and pepper. Simmer for about 15 minutes.
Top with mozzarella. I like to cut up the rounds and through the blobs of cheese all over the top. Transfer the skillet to the top rack of the oven and throw on that broiler. It's ready when the cheese is browning and the dish is bubbling—about 5 minutes?
Remove the skillet from the oven and scatter the ripped basil leaves on top. Serve with warm baked bread.
