Make Enchilada sauce by making a roux with the oil and flour. Whisking until roux is smooth. Cook over med/high heat, stirring almost constantly. Mix water and 6 Tbsp of chili powder together. When roux is light brown in color, add the chili water mixture. Whisk until mixture bubbles, thickens and is smooth. Season with 1 tsp salt and garlic powder. Keep warm.
Make filling by browning ground beef. Drain off accumulated fat. Stir in 1 Tbsp chili powder, 1 tsp salt, minced onion and paprika. Mix with beef. Let mixture brown with beef for a few minutes. Add water. Let simmer for a few more minutes. This mixture should be mostly dry.
Preheat oven to 350 degrees F. Grease a large baking dish. Spread a thin, even layer of sauce over bottom of pan.
Fill a tortilla with 1/6th of meat mixture. Drizzle with a tablespoon or so of sauce. Sprinkle with a tablespoon or so of cheese. Roll up tucking sides in as you go. Place in prepared pan. **Warming the tortillas helps make them more flexible. I usually put half at a time in microwave, between paper towels for 30 seconds.
Roll remaining tortillas in same fashion. Pour remaining sauce over and down sides of tortillas making sure to cover each one thoroughly. Top with remaining cheese. Bake for 20 minutes or until sauce bubbles and cheese melts.
Serve Enchiladas on bed of shredded lettuce. Lettuce can be mixed with the optional tomatoes, onions and/or black olives depending on availability and preference.