Cut the French bread into thick slices, about 1 inch thick. Arrange in a buttered baking dish, slightly overlapping.

In a large bowl, whisk together eggs, milk, heavy cream, brown sugar, vanilla extract, and apple pie spice until smooth.

Pour custard evenly over the bread slices. Press down gently, cover with plastic wrap, and refrigerate for at least 2 hours or overnight.

Spread apple pie filling evenly over soaked bread.

In a bowl, combine flour, brown sugar, cinnamon, and salt. Mix in cold butter with a pastry cutter until crumbly.

Preheat oven to 350°F (175°C). Sprinkle streusel over the filling. Bake for 50 minutes until golden brown and custard is set.