Strata with Chard, Sausage and Caramelized Onions

INGREDIENTS

• 5 Tbs. extra-virgin olive oil
• 2 large yellow onions, halved and very thinly
• sliced
• 4 oz. French bread, cut into 1-inch cubes
• 12 oz. sweet Italian sausage, casings removed
• 3 garlic cloves, minced
• 6 cups roughly chopped Swiss chard
• 8 eggs
• 2 1/2 cups half-and-half
• 1 1/4 cups shredded fontina cheese
• 1/2 tsp. kosher salt
• 1/8 tsp. freshly ground pepper