Preheat the oven to 350°F (175°C) and arrange the mini phyllo tart shells on a baking sheet.
In a medium mixing bowl, combine the shredded cheddar cheese, crumbled bacon, green onions, mayonnaise, and ranch seasoning mix. Stir until well combined.
Spoon about 1 tablespoon of the filling mixture into each mini phyllo tart shell, ensuring they are evenly filled but not overflowing.
Bake the filled tart shells in the preheated oven for 8-10 minutes, or until the cheese is melted and the edges of the phyllo shells are lightly golden.
Remove the baking sheet from the oven and let the taco ranch bites cool for 2-3 minutes. In a small bowl, mix the sour cream and chopped parsley, then dollop a small amount onto the center of each bite for garnish.
Serve the taco ranch bites warm, either as an appetizer or snack, and enjoy the crispy, cheesy, and savory flavors.