Place foil on a small baking sheet. Turn on the broil setting in the oven. Evenly space out three jalapeños on the sheet tray.
Put the sheet tray on the highest of the oven rack. About 15 minutes, roast the jalapenos till the skins are brown and blister. Turn the tray over to ensure all sides are roasted.
Put the roasted chili’s in a small-bowl and cover tightly with plastic-wrap. Let them cool to room temperature. The skins will be easier to peel due to the heat trapped.
After the chili has cooled, take out the stems and skin. Leave the seeds if you prefer a spicy chili. To make a milder chili, remove the seeds and discard them. Set the jalapenos aside.
Add olive oil, diced onions, minced garlic and cumin to a large microwave-safe bowl. Mix to combine. Microwave for 3 minutes. Stir and cook 2 more minutes till the onions are tender. Add to slow cooker.
To the slow cooker, add chicken breasts, ½ cup of roasted chilies and corn, 1 cup white beans, and ½ cup chicken stock. Blend ½ cup of the roasted green chilies and roasted jalapenos, 1 cup beans, and ½ cup chicken stock in a blender until smooth. This should take about 45 seconds. You can also add to a slower cooker.
Add salt and pepper the slow cooker. Cover and cook on high for 3 to 6 hours or low for 6 minutes. Take out the chicken pieces and cut them into cubes.
Add it back to slow cooker and stir to combine. Season chili with salt and pepper to taste. Add toppings to your chili as you like.