No cans of chili here. This dip is simply delicious. Cook's Note: This can also be made a day or two in advance - the flavors just keep on getting better.
In a large skillet, brown the sausage until golden brown and crumbled into small pieces. Drain off excess oil. Add the taco seasoning, cayenne, black beans, salsa, and water if it seems like it needs a little more liquid (this will depend on what kind of salsa you use). The consistency should be like a very thick chili.
Melt the butter in a small saucepan over medium high heat. Add the flour and stir to form a paste. Slowly stream the milk in a little bit at a time, whisking a little bit after each addition. The sauce should thicken up gradually - continue to whisk in the liquid in small amounts and simmer until the sauce is thick enough to stick to the back of the spoon. Stir in the cheese until melted. Add the cheese sauce to the chili in the skillet from step one. Mix until well combined - stir in cilantro or green onions to taste.
Transfer to a mini slow cooker (perfect for parties!) or a serving dish. Or just keep it on the stove so it stays warm.