Lightly coat a 6-quart crock pot with nonstick spray. Spread 1/2 cup tomato sauce on the bottom of the crock pot—the layer will seem very thin. In a small bowl, beat the cottage cheese together with the eggs.
Create the first veggie lasagna layer in the crock pot as follows: 1 layer of eggplant “noodles”; one-third of the cottage cheese (about 2/3 cup); one-third of the bell peppers and onions; one-third of the mozzarella; 1/2 cup tomato sauce.
Create the second veggie lasagna layer, this time using zucchini: 1 layer of zucchini “noodles”; one-third of the cottage cheese; one-third of the bell peppers and onions; one-third of the mozzarella; 1/2 cup of tomato sauce.
Create the final layer: 1 layer of eggplant “noodles”; remaining cottage cheese; remaining bell peppers and onions; 1 layer of zucchini noodles; 1/2 cup tomato sauce; remaining mozzarella.
Cover the crock pot and cook on high for 2 to 3 hours, until the eggplant is tender. To test, insert a long, thin knife into the lasagna and ensure the eggplant feels tender. Re-cover, turn off the slow cooker, and let stand until any remaining liquid is absorbed, about 30 minutes to 1 hour. (Note: if you did not grill or broil the vegetables first, you will have a lot of remaining liquid.) To serve, slice and scoop desired portions, then sprinkle with Parmesan cheese and herbs as desired.