For the Streusel Topping

1. Combine the brown sugar, flour, cinnamon, and salt in a medium bowl. Using your fingers, mix until no lumps of brown sugar remain. Rub in the butter with your fingertips until the mixture has a clumpy, crumbly texture. Refrigerate until ready to use.

For the Kugel

1. Preheat the oven to 325°F and set an oven rack in the middle position. Butter a 9 x 13-inch baking dish.
2. Bring a large pot of unsalted water to a boil. Cook the noodles for 6 to 8 minutes, or according to package instructions, until tender. Drain well.
3. In a large bowl, whisk the eggs. Add the sour cream and softened cream cheese and whisk to combine. Add the half & half, sugar, salt, vanilla, and cinnamon, and whisk until completely smooth.
4. Spread the cooked noodles evenly in the prepared baking dish. Pour the custard mixture evenly over top. Cover the dish tightly with aluminum foil and bake for 35 minutes. Remove and discard the foil. The custard should be just set. Sprinkle the streusel topping evenly over the top, making sure to cover all the noodles. Bake for 35 to 40 minutes more, until the streusel topping is crisp. Let cool for about 20 minutes, then cut into squares and serve.
5. Make Ahead: The kugel and topping can be assembled and stored separately in the fridge up to a day ahead of time, and then baked before serving. (The kugel with the streusel topping may also be fully cooked a day ahead of time and reheated, however the texture will be denser than if baked fresh. To reheat, cover with foil and place in a 325°F oven for 25 minutes; remove and discard the foil, and continue baking for 20 to 25 minutes more, or until warm throughout and crisp on top.)