Prepare the Strata Base

1. Preheat Oven: Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking dish with cooking spray or butter.
2. Cook the Sausage: In a skillet, heat the olive oil over medium heat. Add the sausage and cook, breaking it up with a spoon, until browned and cooked through (about 5-7 minutes). Drain any excess fat and set aside.
3. Cube the Bagels: While the sausage cooks, cube the bagels into bite-sized pieces and place them in the prepared baking dish.
4. Add Cheese and Chives: Sprinkle the shredded cheddar cheese, crumbled goat cheese, and chopped chives evenly over the bagel cubes.

Prepare the Egg Mixture

1. Whisk the Eggs: In a large bowl, whisk together the eggs, milk, salt, and pepper until well combined.
2. Combine the Egg Mixture and Sausage: Pour the egg mixture over the bagels and cheese in the baking dish. Add the cooked sausage and gently toss to combine, ensuring the bagels are well-soaked.

Bake the Strata

1. Let It Set: Let the strata sit for about 10 minutes to allow the bagels to soak up the egg mixture.
2. Bake: Bake the strata in the preheated oven for 45-50 minutes, or until the eggs are set and the top is golden brown and slightly crispy.
3. Cool: Let the strata cool for a few minutes before serving.