Add the two drained tins of white beans to the slow cooker, along with the chopped onion, garlic, tomatillo salsa, vegetable stock, and finely chopped jalapeños (you can add a few less jalapeños to begin with if you're sensitive to spice). Cook on high for 4 hours.
Add the grated smoked cheese and diced tomatoes, as well as a few more jalapeños if you think it needs more spice. Cook for a further 30 minutes. If desired, serve topped with avocado and coriander, with tortilla chips for dipping.
