Preheat oven to 350 degrees. Butter 8x8 inch baking dish. Place 8 baguette slices in bottom of dish; press 2 baguette slices onto each side.
Melt 1 tablespoon butter in large pot over medium-high heat. Add spinach, toss until just wilted, about 3 minutes. Transfer spinach to strainer; cool. Squeeze spinach dry. Transfer to medium bowl.
Heat same pot over medium-high heat. Add sausage, saute until cooked through, breaking up, about 7 minutes. Mix into spinach; mix in 1 cup cheese and peppers. Spread atop baguette slices in bottom of dish.
Whisk eggs in medium bowl to blend. Whisk in last 4 ingredients. Pour over spinach mixture and stir lightly with fork to distribute evenly. Sprinkle remaining 1/2 cup cheese over top.
Bake torta until puffed up and golden and center is set, about 55 minutes. Remove from oven and let rest 15 minutes before serving.