Heat the avocado oil in a large 12-inch skillet over medium-high heat.
Add the ground turkey. Cook for 5 to 7 minutes, breaking it into small crumbles as it cooks, until no pink remains.
Add the red and yellow bell peppers. Cook for about 3 minutes, stirring occasionally, until they begin to soften.
Add the zucchini and yellow squash. Cook for 4 to 5 minutes, stirring occasionally, until the vegetables are crisp-tender.
Sprinkle the taco seasoning over the turkey and vegetables. Pour in the water and stir until the seasoning evenly coats the mixture.
Stir in the drained and rinsed black beans. Cook for 2 to 3 minutes, until the beans are heated through.
If excess liquid remains in the skillet, continue cooking uncovered for 1 to 2 minutes, until most of it has evaporated.
Sprinkle the cheddar cheese evenly over the top. Reduce the heat to low, cover, and cook for 2 to 3 minutes, until the cheese has melted.
Remove from the heat and serve warm.
