Spray a 9x13 baking dish with avocado oil.
Preheat your oven to 375 degrees f.
Heat a large skillet over medium-high heat.
Cook the beef until no longer pink, crumbling the meat as you go with a wooden spoon. Drain any excessive grease.
Add in the onion, celery, bell peppers, garlic, then continue to cook over medium heat, for about 4 more minutes.
Stir in the diced tomatoes with their juice, peas, oregano, paprika, and most of the parsley. Reserve some parsley to garnish your dish. Season with sea salt and pepper to taste.
Simmer over medium heat until the sauce thickens a bit, about 10 minutes.
Meanwhile, boil or steam the cauliflower florets in salted water until very tender. Drain really well and stir in the butter. Using a potato masher, mash your cauliflower until smooth, then season with sea salt and pepper to taste. Alternatively, you can transfer your cooked cauliflower to a blender or food processor, then pulse until just pureed.
Spoon your meat and veggie mixture into your prepared baking dish then spoon the cauliflower mash on top, leveling it with a spoon, as shown in the photos.
Bake for about 20 minutes in your preheated oven, or until bubbly and golden.
Garnish with remaining fresh parsley.
Enjoy!