Preheat oven to 350°F.

In a skillet over medium-high heat, add ½ lb ground beef and break it up with a spatula. Cook until no longer pink. Drain off excess fat.

Add the entire (10‑oz) can diced tomatoes and green chiles (undrained) and 2 Tbsp taco seasoning to the skillet. Stir to combine and cook until most of the liquid is absorbed, about 2–3 minutes.

Remove the skillet from heat and let the beef mixture cool slightly (about 3–5 minutes). Stir in 1/3 cup bottled ranch dressing until evenly distributed.

Spoon the beef mixture into the bottom of the frozen 9‑inch deep dish pie crust and spread it into an even layer.

Sprinkle 1/2 cup shredded cheddar cheese evenly over the beef mixture.

In a medium bowl, whisk together 3 eggs and 1 cup heavy cream until smooth and combined.

Pour the egg and cream mixture evenly into the pie crust over the meat and cheese.

Place the quiche on a baking sheet (to catch any spills) and bake in the preheated 350°F oven for 1 hour, or until the center is set and a knife inserted near the center comes out mostly clean.

Remove from the oven and allow the quiche to rest 5–10 minutes before slicing and serving.