1 pound processed cheese (such as Velveeta), cut into large cubes
1 pound pepper jack cheese, shredded (about 4 cups)
2 cups whole milk
1 teaspoon ground cumin
Tortilla chips, for serving
Combine the processed cheese, pepper jack, milk and cumin in a small slow cooker. Cook on low, 1 1/2 hours.
Uncover and stir well until completely smooth. If the queso is still lumpy, cover and continue cooking on low, stirring every 15 minutes, until all the cheese is melted and smooth. Keep the slow cooker on warm. Serve the queso with chips.