1 loaf (one-pound) unsliced dense white bread (such as pullman), crusts removed and cut into 1-inch cubes
4 tablespoons unsalted butter
1/2 pint fresh blueberries
1/2 pint fresh raspberries
2 bananas, sliced
Maple syrup (optional)
Preheat oven to 250 degrees. Place a rimmed baking sheet in the oven to warm. In a medium bowl, whisk together eggs, buttermilk, salt, and vanilla. Stir in bread.
In a large saute pan set over medium heat, melt 2 tablespoons butter. Place half of the bread mixture in pan; cook, turning occasionally with a spatula, until browned on all sides. To keep warm, transfer to the oven. Cook remaining bread in the remaining 2 tablespoons butter as before.
Thread bread cubes onto skewers alternating with blueberries, raspberries, and banana slices. Serve immediately with maple syrup, if desired.