- Butter, room temperature, for baking dish
- 1 loaf (3/4 pound) brioche or challah, cut into 2-inch-thick slices and halved crosswise
- 4 fully cooked chicken sausages (about 12 ounces total), thinly sliced
- 8 large eggs
- 2 1/2 cups whole milk
- 1/2 cup pure maple syrup, plus more for serving (optional)
- Coarse salt and ground pepper
- 2 tablespoons olive oil
- 2 teaspoons raspberry preserves
- 2 tablespoons red-wine vinegar
- 1 large head Boston lettuce (about 1 pound), torn into bite-size pieces
- 1 cup seedless red grapes, halved
- Butter a 2-quart shallow baking dish; arrange bread slices in dish, overlapping slightly. Place sausage slices between bread slices.
- In a large bowl, whisk together eggs, milk, maple syrup, and 1 teaspoon salt until combined. Pour egg mixture over bread and sausage, pressing down on bread to submerge. Cover dish tightly with plastic wrap; refrigerate at least 2 hours (or up to overnight).
- Preheat oven to 350 degrees. Remove plastic wrap, and place baking dish on a rimmed baking sheet. Bake until strata is puffed and set in center, about 1 1/2 hours (tent with aluminum foil if browning too quickly). Let cool 10 minutes.
- While strata cools, whisk together oil, preserves, and vinegar in a large bowl; season with salt and pepper. Add lettuce and grapes; toss to combine. Serve strata with salad and, if desired, additional syrup on the side.
Overlapping the bread slices gives the strata a nice golden-brown crust, even as it soaks up plenty of the egg mixture.