In a mixing bowl, stir together the softened cream cheese, sour cream, refried beans, 1/2 of the Cheddar cheese, 1/2 of the Monterey Jack cheese, 1/2 of the green onions, and the taco seasoning.
Spread the mixture into a baking dish (9x13 or 8x8). Sprinkle the remaining cheese over top.
Bake until dip is hot and bubbly and cheese is golden brown, 20 to 25 minutes.
Garnish with the remaining green onions. Serve with tortilla chips.