Melt the remaining 2 tablespoons butter in a large saucepan over medium heat. Add the oil separated from the chili crisp. Sprinkle in flour and whisk to combine. The mixture will look like very wet sand. Cook for about 1 minute, whisking often. Slowly pour in about 1 cup of the half-and-half, while whisking constantly until smooth. Slowly pour in the remaining half-and-half and the milk, while whisking constantly until combined and smooth. Season with salt and pepper.
Melt the remaining 2 tablespoons butter in a large saucepan over medium heat. Add the oil separated from the chili crisp. Sprinkle in flour and whisk to combine. The mixture will look like very wet sand. Cook for about 1 minute, whisking often. Slowly pour in about 1 cup of the half-and-half, while whisking constantly until smooth. Slowly pour in the remaining half-and-half and the milk, while whisking constantly until combined and smooth. Season with salt and pepper.
