In a large skillet, heat neutral oil over medium heat. Sauté onion and jalapeños until translucent, about 4-5 minutes. Add garlic and cook for 1 minute until fragrant. Stir in tomato paste, cooking for 2 minutes. Add ground beef, taco seasoning, and salt, cooking until browned, about 6-8 minutes. Remove from heat and allow to cool.

In a mixing bowl, combine cheddar and pepper jack cheese. Mix flour with lime juice in another bowl to create a glue-like consistency. Microwave corn tortillas for 30 seconds to make pliable. Spoon beef mixture onto each tortilla, roll tightly, and seal with flour paste.

Whisk together sour cream, cilantro, and lime juice in a separate bowl. Season with salt to taste, cover, and refrigerate while cooking taquitos.

Preheat oven to 400°F if baking or heat oil in frying pan to 375°F. For baking, place taquitos on a lined sheet, brush with oil, and bake for 15-20 minutes until golden. For frying, cook in batches for about 3-4 minutes per batch until crispy.

Serve hot, garnished with cilantro and alongside lime crema, guacamole, or salsa.