Spinach Dip Hot Bread

Ingredients
- 6 tablespoons unsalted butter, divided
- 2 tablespoons all-purpose flour
- ¾ cup whole milk
- ¾ cup heavy cream
- 1 ¼ teaspoons kosher salt, divided
- ¾ teaspoon ground white pepper, divided
- 1 ½ cups chopped yellow onion (about 1 medium onion)
- 10 ounces fresh baby spinach
- 14 ounces Der Smoked Alpen Cheese, shredded
- 1 (24-ounce) round sourdough boule
- 1 tablespoon chopped Calabrian chiles (from a jar)
- ⅓ cup shredded low-moisture part-skim mozzarella cheese
Instructions
- Preheat your oven to 450°F. In a small saucepan, melt 2 tablespoons of butter over medium heat. Whisk in the flour until smooth, about 1 minute.
- Slowly add the milk and cream, whisking constantly to prevent lumps. Bring the mixture to a boil, then reduce heat to low and simmer for 20 minutes, stirring occasionally, until thickened. Stir in ¾ teaspoon salt and ¼ teaspoon white pepper, then remove from heat.
- Meanwhile, melt the remaining ¼ cup of butter in a large Dutch oven over medium heat. Add the chopped onion and cook, stirring occasionally, until softened, about 6 minutes.
- Add the spinach and cook, stirring often, until the liquid evaporates and the pot is dry, about 4 minutes.
- Pour the milk mixture into the Dutch oven with the spinach and onion. Stir well to combine.
- Mix in the Der Smoked Alpen Cheese and the remaining salt and pepper. Remove from heat.
- Cut the sourdough boule into 5 slices, each about 1-inch thick. Cut almost all the way through, leaving the bottom crust intact. Slice each piece in half lengthwise, again leaving the bottom crust intact.
- Arrange the boule on a baking sheet lined with parchment paper or foil. Spoon the spinach-cheese mixture evenly between the bread slices. Top with Calabrian chiles and mozzarella.
- Bake in the preheated oven until the top is golden brown and the filling is hot and bubbly, 7-10 minutes.