Preheat oven to 400°F. Butter a 3 qt baking dish with 1 tablespoon butter. Set aside.
Place cubed bread on a rimmed baking sheet and toast in the oven for 10-15 minutes, stirring halfway through. Remove from oven and set aside to cool.
In a medium skillet add the sausage and brown over medium-high heat, about 10 minutes. Remove with a slotted spoon to a bowl and set aside.
In the same skillet add 2 tablespoons butter, onion, and red pepper and saute over medium-high heat until the onions are translucent, about 8-10 minutes. Add the garlic, Greek Freak Mediterranean Rub, and salt. Stir to combine. Remove from heat.
In a large bowl whisk the eggs, milk, cheese, and parsley until well combined. Stir in bread cubes, sausage and onion mixture. Pour into prepared baking dish. Cover tightly and refrigerate 2 hours, or overnight.
Preheat oven to 400°F. Bake uncovered 45-50 minutes.