Coarsely grate the white cheddar cheese. Combine the grated cheese and corn starch in a large microwave-safe bowl. Toss with a fork to combine.
Add the half and half, mayonnaise, cumin and onion powder and stir to combine.
Microwave on high power for about 1 minute, until cheese is mostly melted. Stir well and return to microwave for 1 more minute. Stir until all cheese is melted and the mixture is smooth.
Add red peppers, 1-2 tablespoons of the jalapeños and crushed red pepper. Stir to combine. Add a little more half and half if the mixture is too thick. Taste and add more jalapeños and/or crushed red pepper if more heat is desired. Serve with tortilla chips.
Notes
See Café Tips above for more detailed instruction, how to make ahead and extra tips.