"This is actually better than stuffed shells made with just cheese. The texture and taste of the cauliflower mash makes this creamy, filling, and comforting -- and there's still plenty of cheese to get your fix!
It's a great source of veggies, a perfect meatless Monday option, and freezes well (if you have any leftovers...which has only happened once).
This is actually requested over full cheese versions among my friends now!"
Fill a large pot with lightly salted water and bring to a rolling boil. Stir in pasta shells and return to a boil. Cook pasta uncovered, stirring occasionally, until tender yet firm to the bite, about 9 minutes. Drain.
Preheat the oven to 375 degrees F (190 degrees C).
Place a steamer insert into a saucepan and fill with water to just below the bottom of the steamer. Bring water to a boil. Add cauliflower, cover, and steam until very soft, 5 to 8 minutes.
Heat 1 tablespoon oil in a skillet over medium-low heat. Add sliced garlic; cook and stir until golden, about 5 minutes. Add crumbled red pepper pods. Raise heat to medium-high and add cauliflower; cut up and smash with a spatula. Add 1 teaspoon salt. Cook and stir, mashing occasionally, until mixture has rough consistency of mashed potatoes, about 5 minutes more. Remove from heat and transfer to a large bowl.
Rinse and dry skillet. Add 1 tablespoon oil and place on medium heat. Add 2 cloves minced garlic; cook and stir until golden, about 2 minutes. Add spinach and stir until reduced down, about 3 minutes. Add spinach and garlic to the bowl with cauliflower mixture.
Stir Italian cheese blend, ricotta cheese, 3 tablespoons basil, Parmesan cheese, kosher salt, and black pepper into the spinach-cauliflower mixture to make the filling.
Mix remaining 2 cloves minced garlic, remaining 2 tablespoons basil, and oregano into the can of crushed tomatoes. Pour 1/3 of tomato sauce mixture into the bottom of a 9x13-inch glass baking pan.
Stuff cooked pasta shells with the filling and place seam-side up in the baking dish. Spoon remaining tomato sauce over shells and in any gaps between. Cover tightly with aluminum foil.
Bake in the preheated oven for 30 minutes. Remove foil and bake until top is bubbling, about 15 minutes more.