Wash and dry chile; place on an aluminum foil-lined baking sheet. Bake at 425° for 45 minutes. Place in a plastic bag; close tightly, and let stand 10 minutes. Peel chile; remove core and seeds. Chop chile.

Step 2

Combine chile and the next 5 ingredients in a Dutch oven. Bring to a boil; cover, reduce heat, and simmer 20 minutes or until the potato is tender. Drain, reserving 3 cups liquid. Set half of the potato mixture aside. Mash the remaining half of the potato mixture. Set aside.

Step 3

Melt butter in the Dutch oven over low heat; add flour, stirring until smooth. Cook 1 minute, stirring constantly.

Step 4

Gradually add reserved potato liquid, half-and-half, and milk; cook over medium heat, stirring constantly, until the mixture is thickened and bubbly. Add reserved potato mixture, stirring well. When heated, ladle into individual soup bowls. Sprinkle with cheese.