Blend onion, garlic, tomato sauce, garam masala and salt. Put in an electric pressure cooker with soaked chickpeas and diced sweet potatoes.

ETA: I forgot ginger, which is blended with the items in the first step.

Edited with more details:

1. In a blender liquify onions, garlic, ginger, tomato sauce. I used two small onions, a giant clove of garlic, about 2 tbsp equivalent volume of ginger, a 500 mL jar of homemade tomato sauce (just tomato no seasoning).

2. Put the blended stuff and extra water to rinse the blender (if needed) in the EPC. You want enough liquid to cover the beans and potatoes. Add soaked beans (my volume soaked was about a liter, have no idea what the dry quantity was). Add peeled and diced sweet potatoes (2 lbs maybe?). I seasoned it with about 1 tbsp fresh ground garam masala and maybe half a tbsp of salt?

3. I cooked for 40 mins on high pressure regular heat.

4. Stir and taste after cooking, you will probably need more salt.

Never baked them haha. I just put them in my curries sometimes

Very similar in texture and use as other potatoes. They are softer and create a looser mash. So, if you have something that would be good with potato, and a sweet component to the flavor would compliment the other aspects of the meal, sweet potatoes are a great thing to give a shot in place of normal ones. They make a number of good desserts as well.

Welcome to the wonderful world of sweet potatoes! They make a great thickener in stews as well if you cook them long enough to break them down.