In a medium bowl, combine the cream cheese, pepper jack, lime juice, garlic powder, onion powder, cumin, and 1/2 teaspoon salt and stir well. Cover and chill while preparing the jalapeños.
To make the poppers:
Trim off and discard the top and bottom of each jalapeño. Cut each jalapeño into 1-inch rings. Remove the seeds and white inner ribs from each ring (wearing gloves is recommended).
Line a rimmed baking sheet with parchment paper. Pack about 1 teaspoon cream cheese into each jalapeño ring, filling it completely and smoothing the surface.
Fill three small bowls separately with milk, flour, and breadcrumbs. Working with one popper at a time, dip in milk, then coat with flour. Transfer to the prepared sheet and repeating with remaining jalapeño rings. Let the coating sit for 5 minutes.
Working with one at a time, return floured jalapeño rings to milk, turning to coat. Transfer to breadcrumbs, pressing the breadcrumbs to form an even coating. Repeat with the remaining poppers.
In a large pot, Dutch oven, or deep fryer, bring 2 inches of oil to 350 degrees. Drop 4 to 6 poppers in the oil at a time, stirring as necessary until golden brown all over, about 5 minutes. Transfer to a paper towel-lined baking sheet and sprinkle with salt. Serve with ranch dressing if desired.
Jalapeños: On the Scoville scale, the measurement of how spicy a pepper is, jalapeño peppers are rated mild to moderate. To minimize the heat, be sure to carefully remove all seeds and white membrane inside (wear gloves if you need to).
Oil: Choose a neutral cooking oil with a higher smoke point such as vegetable oil, canola oil, or avocado oil.
Yield: This recipe makes about 30 poppers or 10 servings (3 poppers per serving).
Storage: Jalapeño poppers are best enjoyed right when they are made, but leftovers can be stored in the refrigerator for up to 4 days. Reheat in a 325-degree oven for 10 to 15 minutes, until heated through. Or microwave for 20 to 30 seconds (they won't be crispy anymore, but they will still taste good).
Make ahead: The filling can be made up to 3 days ahead. Store covered in the refrigerator. The jalapeños can be prepped and filled with cream cheese the day before. Hold off on the breading and frying until the day you want to eat them.
Keeping warm: After frying, and until serving time (up to 1 hour in advance), place the fried poppers on a baking sheet in a 225-degree oven.
Oven-baked: To skip the deep-fryer, preheat an oven to 400 degrees. Arrange stuffed and breaded poppers on a wire rack set over a baking sheet lined with foil. Bake until hot and crispy, about 15 to 20 minutes.