To make the strawberry jam, combine chopped strawberries, sugar, and water in a pot over the stove. Let simmer for 15 minutes, stirring occasionally until the strawberries break down to a jam-like texture.
For the strawberry topping, place strawberries, sugar, and lemon juice in a bowl. Cover and refrigerate for at least 30 minutes, stirring occasionally.
Spray a baking dish with cooking spray. Place half of the bread cubes into the dish.
Pour half of the strawberry jam on top of the bread. Add the rest of the bread cubes.
Whisk together eggs, cream, vanilla, sugar and salt in a large bowl.
Pour the egg mixture over the bread cubes, pushing them down so that the bread is fully covered. Pour the rest of the jam on top.
Cover the casserole and refrigerate for 30 minutes.
Remove from the refrigerator and uncover the casserole. Bake for 40 minutes, until it us puffed up and golden brown.
Let cool for 5 minutes. Stir the strawberry topping and pour it over the casserole once it has cooled.
Dust with powdered sugar, cut into square pieces, and enjoy.