Slow Cooker Beans and Barley

Yesterday, in a moment of reckless abandon, I put 1 cup of each of the following into the slow cooker:
kidney beans
green lentils
white beans
red lentils
unhulled barley

I then added:
3 huge carrots, sliced into coins
2 potatoes cuts into cubes

I covered the whole thing with boiling water (I had gotten a late start and didn't want to take any chances) and put it on high for about 6 hours.

Knowing this would be hearty but bland, I set about making a gravy. I was experimenting so here's the rough recipe. You may need to make your own adjustments.

In a bit of olive oil saute:
1 large onion, chopped
When the onion begins to brown or stick add a bit of water and toss in:
4 cloves garlic, minced
Let these simmer, without burning, for about 3 minutes. Add more water if necessary. Add in:
1 tsp thyme
1 Tbs Braggs
4 cups of water (I used water left over from boiling potatoes)

I ran this through the blender, added some cooked mashed potato to thicken and then put it back in the pot. Once this is heated, whisk in:
3 Tbs miso

This made a tasty gravy that went well over the bean concoction.