Preheat the oven to 400 degrees. Bring a large pot of water with a large pinch of salt to a boil. Remove the ground beef from the refrigerator and bring to room temperature. Halve, peel, and finely chop the onion. Mince or grate the garlic. Remove and discard the kale ribs and stems, then roughly chop the leaves.

Cook the penne: Add the penne to the boiling water and cook for 9-11 minutes, until al dente. Drain.

Meanwhile, heat a drizzle of oil in a large pan over medium heat. Add the chopped onion to the pan and cook, tossing for 4-5 minutes, until softened. Add the beef, garlic, oregano, and as much chili flakes as you like to the pan. Cook, breaking up the meat into pieces, until browned. Season with salt and pepper.

In a large bowl, toss together the drained penne, beef mixture, tomatoes, kale, and half the mozzarella. Season with salt and pepper.

Transfer to a lightly oiled baking dish (ours is 9”x13”) and sprinkle with the panko and remaining mozzarella. Place in the oven for 12-15 minutes, or until browned and bubbling. Enjoy!