Toad in the Hole

In a bowl, combine the milk, eggs, egg white and mustard. Using an immersion blender, blend until incorporated, about 1 minute. Add the flour and the 1 tsp. salt and blend for 30 to 60 seconds, scraping down the sides of the bowl as needed. Cover the bowl with plastic wrap and refrigerate the batter for 2 hours.

Preheat an oven to 425ºF.

In a 10-inch fry pan over medium heat, warm 1 tsp. of the oil. Add the sausages and brown on all sides, 8 to 10 minutes. Transfer to a plate. Wipe out the pan with paper towels. Return the pan to medium heat and warm 1 tsp. of the oil. Add the bell pepper and cook, stirring occasionally, until tender, 8 to 10 minutes. Transfer to the plate with the sausage. In the same pan over medium heat, warm 1 Tbs. of the oil. Add the spinach, season with salt and pepper, and cook until wilted, 1 to 2 minutes. Transfer to the plate.

Pour the remaining 2 Tbs. oil into a 12-inch fry pan and place in the oven until the oil is hot and just smoking, 10 to 15 minutes. Remove the batter from the refrigerator and stir in the cheese. Carefully remove the pan from the oven. Add the sausages, bell pepper and spinach to the pan, then pour in the batter. Return the pan to the oven and bake until the batter is puffy and golden brown, 25 to 30 minutes; do not open the oven door early as this will cause the toad in the hole to deflate. Garnish with the chives and serve immediately. Serves 4 to 6.