Start by heating 2 tablespoons of olive oil in a large skillet over medium heat. Allow the oil to warm for about 1-2 minutes until shimmering.

Add the finely chopped onion to the skillet and sauté for 2-3 minutes until it becomes translucent.

Incorporate 3 cloves of minced garlic into the skillet, cooking for an additional 30 seconds.

Introduce 1 pound of ground beef to the skillet and cook for 5-7 minutes, stirring occasionally until browned.

Season the cooked beef with salt, black pepper, cumin, smoked paprika, oregano, and optional red pepper flakes. Mix well.

Add diced bell pepper and zucchini to the skillet and cook for about 5 minutes until slightly tender.

Fold in the halved cherry tomatoes and pitted Kalamata olives, cooking for an additional 2 minutes.

Remove the skillet from heat and mix in 2 tablespoons of chopped fresh parsley and the juice of half a lemon.

Transfer the stir-fry to a serving platter, topping it with crumbled feta cheese and toasted pine nuts.