Spread the refried beans evenly across the bottom of a shallow serving dish to form the first layer.
Spoon the guacamole over the beans and smooth it into an even layer.
Use 3/4 cup of the sour cream to create the next layer, spreading it gently over the guacamole.
Sprinkle the shredded cheddar cheese evenly over the sour cream layer.
Add the diced tomatoes as the next layer, distributing them across the surface.
Scatter the sliced black olives over the tomatoes.
Finish with the chopped green onions as the final layer.
Place the remaining 1/4 cup sour cream in a small zip-top bag, snip off one corner, and pipe concentric circles over the top. Drag a toothpick from the center outward to form the spiderweb design.
Serve with tortilla chips on the side.