Heat oven to 200C/180C fan/gas 6. Arrange the tortilla chips over two-thirds of the tray, spoon most of the salsa on top and scatter over half of the cheese.
Mix the remaining salsa with the red pepper and beans, and tip onto the empty third of the tray. Scatter over the rest of the cheese. Bake for 10-15 mins or until the cheese has melted. Scatter the avocado over the beans and add dollops of the soured cream to serve.