Heat a tablespoon of the olive oil on a wide, heavy-bottomed skillet or sautee pan. Once very hot, add the summer squash pieces and season with salt and pepper. Cook, stirring occasionally, about 2 minutes, or until just browned in some areas. Remove from pan.
Add another tablespoon of olive oil and scatter the onion. Season with a pinch of salt and pepper. Once slightly browned in parts and milky-white or translucent, remove from pan.
Add another tablespoon of olive oil and add the minced garlic. Once fragrant, after a few seconds, add the tomatoes and a pinch of salt and pepper. Cook, stirring occasionally, 2-3 minutes or until juices have slightly cooked down. Add the peas and cook another 1-2 minutes. Return the squashes and onions to the pan and cook until warmed through and slightly more softened. Taste for seasoning. Serve with a drizzle of olive oil and the fresh herbs with crusty bread.
