*For a spicy sauce, use 1 New Mexico and 7 California chiles. Eliminate the New Mexico chile for a milder sauce. Wearing gloves, use a small knife to remove chile stems and seeds, then wash the chiles well. Place in a saucepan with the water and bring to a boil over high heat; boil for 5 minutes, then allow to sit for 10 to 15 minutes. Whirl the water and chiles in a food processor or blender, in batches if necessary, for 20 to 30 seconds, or until the skins are finely chopped. Pass through a strainer, pressing the chile pieces through with a wooden spoon. In a medium skillet, make a roux by combining the flour and oil. Saute over low heat for 2 minutes, then add the garlic, chile mixture, oregano and vinegar. Stir well and simmer for 15 to 20 minutes. The sauce will keep in the refrigerator, tightly covered, for about 5 days, or it can be frozen for 2 to 3 months.