If your beans are cold, bring them to room temperature. Otherwise, stir in the chili powder then taste the beans and add salt.
For the guacamole, in a small bowl mash the avocados with the garlic, jalapeño, cilantro, lime juice, and salt. Taste and add more salt if desired.
For the pico, stir together the tomatoes, garlic, jalapeño, cilantro, salt, and cumin. Taste and adjust seasonings if desired.
To assemble the dip, take a 9-inch baking dish or skillet and spread along the bottom the refried beans. Evenly spread on top of the beans the guacamole. Evenly spread on top of the guacamole the sour cream.
Evenly pour on top of the sour cream the salsa. Evenly spoon on top of the salsa the pico de gallo. Sprinkle on top of the pico the shredded cheese. Last, add the green onions and then the black olives.
Serve immediately with tortilla chips. You can also keep covered in the refrigerator for several hours before serving, if you prefer, though it's best fresh.
Notes
Can I substitute Cheddar cheese and Monterey Jack cheese for the Colby Jack? Yes you can, use 1 cup of each. Can you freeze seven-layer dip? No, it will not freeze very well. I have ripe roma tomatoes, can I use that instead? Yes, I'd use 1 ripe tomato.