Cook the spaghetti squash: Preheat the oven to 400 degrees. Cut spaghetti squash in half lengthwise and remove seeds. Rub inside of squash with olive oil and sprinkle with salt and pepper. Place face down on a baking pan lined with foil. Bake for 30 minutes.

Once spaghetti squash is cooked, scrape out inside "spaghetti" onto a baking pan lined with parchment paper. Pat squash with a paper towel, absorbing any excess moisture, and flattening into a pizza crust.

Bake crust at 400 degrees for 15 minutes.

Meanwhile, prepare the topping. Cook onion and garlic on low heat in 1 tbsp of oil until fragrant, about 1-2 minutes. Turn up the heat to medium and add kale, salt, and pepper. Cook until kale begins to wilt, about 5 minutes more. (Cover pan to cook faster.)

Once spaghetti squash crust is cooked, top with the ricotta, spreading evenly. Add kale mixture on top. Finish with a thing layer of shredded mozzarella cheese.

Bake at 400 degrees for 10 minutes more.