Sheet Pan Layerless Lasagna

Name: Sheet Pan Layerless Lasagna
Prep time: 10 min
Cook time: 50 min
Total time: 1 h
Cuisine: European, Italian, Mediterranean
Ingredients: Shop the Sheet Pan Lasagna Box!; 4 tablespoons olive oil, divided; 1 pound taccole pasta or broken-up sheets of lasagna; 1 clove garlic, chopped; 1 teaspoon Giadzy Spicy Seasoned Salt, divided; 1 (5-ounce) container baby spinach; 1 cup whole milk ricotta cheese; 1 pound spicy Italian sausage, casings removed; 1 red onion, diced; 3 (12.34-ounce) jars Giadzy Passata, or 4 cups tomato puree; 2 ½ cups shredded low-moisture mozzarella, divided; 1 ½ cups freshly grated Parmigiano Reggiano, divided; Kosher salt, for the pasta water