Prep the vegetables by dicing the zucchini and red bell pepper into small, uniform cubes, and finely mincing the garlic clove.
Heat a large cast-iron or stainless steel skillet over medium-high heat and add the avocado oil, swirling to coat the surface.
Add the ground beef to the hot skillet, breaking it apart with a wooden spoon or spatula, and cook until browned and no longer pink.
Stir in the diced zucchini and red bell pepper, cooking for 4-5 minutes until the vegetables are tender-crisp and the beef is fully cooked.
Add the minced garlic, sea salt, black pepper, smoked paprika, and onion powder to the skillet, stirring constantly for 1 minute until the spices are fragrant.
Add the baby spinach to the skillet and toss gently for about 30-60 seconds just until the leaves are wilted and bright green.
Remove from heat immediately and serve warm, optionally garnishing with fresh herbs if desired.