Prep your station: Preheat your oven to 375°F (190°C). Line a large sheet pan with parchment for easy cleanup.
Warm the milk for the cheese sauce and shred your cheeses so everything is ready.
Cook the beef: Heat a large skillet over medium-high. Add the ground beef and cook, breaking it up with a spoon, until browned with some crispy bits, about 5–7 minutes. Drain excess fat if needed.
Add aromatics and spices: Push beef to one side.
Add onion to the empty space and sauté 2 minutes until softened. Stir in garlic for 30 seconds. Add chili powder, cumin, smoked paprika, oregano, salt, and pepper.
Cook 1 minute to bloom the spices.
Simmer and finish: Stir in tomato paste and water (or broth). Simmer 2–3 minutes until thick and saucy. Taste and adjust salt.
Turn off heat.
Make the cheese sauce: In a small saucepan, melt butter over medium heat. Whisk in flour and cook 1 minute. Slowly whisk in warm milk until smooth.
Simmer gently, whisking, until slightly thickened, 2–3 minutes. Off heat, add shredded cheddar a handful at a time until melted. Season with salt and cayenne if using.
Keep warm on low.
Build the base layer: Spread half the chips on the sheet pan. Scatter half the beef, half the beans, and half the corn. Sprinkle with a handful of shredded cheese or drizzle some cheese sauce.
Add the second layer: Repeat with remaining chips, beef, beans, and corn.
Top with the rest of the shredded cheese or more sauce. Layering ensures even coverage and fewer naked chips.
Bake to melt: Bake 6–8 minutes until the cheese is melted and the edges of the chips are toasty. If using only cheese sauce, you can skip baking and assemble directly, but a quick bake warms everything through.
Add fresh toppings: Remove from the oven and immediately top with jalapeño slices, tomato, red onion, avocado, and cilantro.
Drizzle with sour cream and spoon over salsa or pico. Serve with lime wedges.
Serve right away: Nachos are best enjoyed hot. Bring the whole tray to the table and let everyone dig in.