Chop up tomatoes and sweet peppers and add to slow cooker. Sprinkle with salt + pepper to flavor. Cook on high for 1 1/2 hours. Carefully remove tomatoes and peppers to small pot and use an emulsion blender to make it creamy. Careful, the tomatoes are very hot! Alternatively if you don't have an emulsion blender, you can use a regular blender or food processor. Put back in slow cooker.
Add chopped cheese to slow cooker and cook on high for 1 more hour.
Pour into bowl and garnish top with slices of jalapeño peppers. Serve with tortilla chips.