Brown ground beef in a large skillet over medium-high heat. Stirring to break up and brown evenly.
Add taco seasonings and water and stir to combine. Cook for 5 minutes, remove from heat and set aside.
Add butter to a saucepan and whisk in flour. Cook over medium heat. Whisk continually for about 3 minutes.
Add chicken broth, sour cream, heavy cream, salsa verde, cumin and garlic. Continue to whisk, heating until sauce thickens. Remove from heat.
Preheat oven to 350°.
Pour half of sauce in a 9 x 13 inch baking dish.
Spoon ground beef into tortillas and roll up. Place seam side down into sauce.
Pour remainder of sauce over the top of the burritos.
Top with shredded cheese.
Bake, uncovered for 30 minutes.
Remove from oven and rest 5 minutes before serving.
Top with additional sour cream and salsa if desired.