Mix the spices - Combine cumin, chili powder, garlic powder, salt, and cayenne in a small bowl and set aside.
Cook the filling - Heat 1 tablespoon of vegetable oil in a large skillet over medium-high heat. Add the chicken, red bell pepper, green onion, corn, black beans, spinach, and jalapeño. Sprinkle in the spice mix and stir well. Cook for 3 minutes.
Melt the cheese - Reduce heat to medium-low. Add shredded Monterey Jack cheese and stir until fully melted into the filling. Remove from heat and allow to cool for 10 minutes.
Roll the eggrolls - Warm tortillas briefly in the microwave to soften. Spoon filling down the center of each tortilla, fold in the sides, and roll up tightly. Secure each with a toothpick.
Fry to golden - Heat 3 to 4 inches of vegetable oil in a deep pot to 350°F. Fry eggrolls in batches of 2 to 3 for 7 to 8 minutes, turning once, until deep golden brown. Drain on a wire rack.
Make the dipping sauce - Whisk together mashed avocado, mayonnaise, sour cream, buttermilk, vinegar, onion powder, garlic powder, dill, and salt until smooth. Refrigerate until ready to serve.
Serve - Remove toothpicks, slice each eggroll diagonally, and serve immediately with avocado ranch dipping sauce on the side.