Sweet Potato Chili

I came up with this on the fly last night, and it turned out really nice.  Here's the ingredients:

2 medium sweet potatoes-diced to size of your preference
1 onion-chopped
1/2 lb bacon-cooked, and coarsely chopped
1 can black beans, drained
1 can diced tomatoes with green chilis
2 cans water
1 T minced garlic
1 T each: onion powder, cumin, curry powder
1/4 cup corn starch mixed with cold water
Iron dutch oven-if you have one

Fry up the bacon (wasn't there a song about that? anyway).  Take it out of the pan and drain it on some paper towels.  Keep the grease in the pan, and throw in the onion on low heat.  Let it carmelize and brown.  Add the garlic, then the sweet potatoes.  Cover, stirring every few minutes, browning the sweet potatoes until they are almost done. 
Add the rest of the ingredients and cook on low heat for about 45 minutes, stirring often.   Add the bacon to the top, and some  grated cheese and cilantro, or whatever floats your boat.