G and I loved some tacos and we made all types. The go-to standard though was ground beef cooked with Hatch green chiles, garlic, onion powder or fine chopped onion, chile powder, cumin, red pepper if we felt spicy, black pepper and salt. He would add a little bit of water to the beef when it was browning and then use a wooden spatula to ensure it was "fine". Corn is sweet so you have to be judicious with it. We sometimes would mix corn and pintos or corn and black beans too to add. Like Senor Bisi noted -add the toppings or at least have a salad on the side with all those ingredients. Damn. We thought La Tiera white corn shells were the best - low sodium and low carb thin crispy goodness.
Best "real" tacos ever - Rosa's in Noel Missouri across from the Tyson plant. Holy hell.