Brûléed Orange French Toast

INGREDIENTS

• 6 eggs, lightly beaten
• 1 cup heavy cream
• 3⁄4 cup milk
• 3⁄4 cup fresh orange juice
• 1⁄4 cup firmly packed light brown sugar
• 2 tsp. vanilla extract
• 1 tsp. orange zest
• 1⁄2 tsp. salt
• 1 Tbs. Grand Marnier (optional)
• 6 slices brioche, each 1 3⁄4 inches thick
• Softened unsalted butter for cooking and serving
• 6 tsp. granulated sugar
• Maple syrup for serving