1
                        medium or 2 small eggplant, cut into 1/2-inch dice
                                        
                        
                        4 tablespoons
                        olive oil, divided, plus more to taste
                                        
                        
                        2
                        medium onions, cut into 1/2-inch dice
                                        
                        
                        4
                        to 6 garlic cloves, chopped
                                        
                        
                        1/2 bunch
                        basil, tied in a bouquet with kitchen twine + 6 basil leaves, chopped
                                        
                        
                        1 pinch
                        dried chile flakes
                                        
                        
                        2
                        sweet peppers, cut into 1/2-inch dice
                                        
                        
                        3
                        medium summer squash, cut into 1/2-inch dice
                                        
                        
                        3
                        ripe medium tomatoes, cut into 1/2-inch dice