01 - Combine whole milk and heavy cream in a medium saucepan over medium heat. Bring just to a simmer without boiling.
02 - Add cream cheese to the hot milk mixture, whisking continuously until completely melted and smooth.
03 - Gradually add shredded white American cheese one handful at a time, whisking constantly until fully melted and the dip achieves a smooth, creamy consistency.
04 - Stir in diced jalapeño, green chilies, onion, and garlic. Cook for 2-3 minutes with frequent stirring until vegetables soften.
05 - Add ground cumin, chili powder, salt, and white pepper. Taste and adjust seasoning as desired.
06 - Reduce heat to low to keep warm. If dip thickens excessively, whisk in a small splash of milk to reach desired consistency. Serve immediately with tortilla chips.