Step 1

Spread bread slices on a baking sheet; let stand at least a few hours and up to overnight. Melt butter in a large ovenproof, nonreactive skillet (like an 11-to-12-inch enameled cast iron) over medium heat. Add 1 cup brown sugar, 1/4 teaspoon salt, and lemon juice. Cook, stirring, until sugar dissolves, then bring to a boil; cook 1 minute.

Step 2

Add apples and cook, turning occasionally, until they begin to soften and brown a bit and liquid thickens, about 12 minutes. Let cool 30 minutes.

Step 3

In a wide, shallow dish, whisk together eggs, milk, remaining 2 tablespoons brown sugar, vanilla, and 1/4 teaspoon salt. Dip bread in mixture, turning to coat. Arrange atop apples, shingling in concentric circles. Pour remaining mixture on top. Cover; refrigerate at least 2 hours and up to 24.

Step 4

Preheat oven to 350°F. Sprinkle French toast with cinnamon and bake, uncovered, until set and golden on top, 35 to 45 minutes. Let stand 15 minutes. Dust with confectioners' sugar; serve with yogurt, pecans, and fruit.