Preheat oven to 400°; boil a large pot of salted water, add a box of pasta + cook 10-12 min or until al dente; drain + return to pot

Meanwhile, open the packages of cauliflower rice to vent + heat in microwave 90 sec (careful—it'll be hot!); if using a skillet, warm 2 min with 1 tbsp water

Add 1 cup of sauce, 2 packages of riced cauliflower + salt/pep to pasta; toss to coat noodles

Transfer pasta mixture to a lightly oiled baking dish + sprinkle on 1/2 of a block of grated cheese (or more!); bake 15-17 min until cheese is melted + bubbling

Top with chopped chives; let set 5 min before scooping + digging in—yum!