In a Instant Pot (pressure cooker), cook the chicken in water on the "meat" setting for 8-10 minutes. (Cooking time varies depending on the size of your pressure cooker.). If using a slow cooker, cook on high for 4-6 hours or low for 6-8 hours.
Remove the chicken from the Instant Pot or slow cooker. In a separate bowl, use a fork to shred the chicken.
Add the buffalo sauce and stir to combine.
Spoon the chicken into individual lettuce boats. Top with blue cheese (or low calorie Ranch dressing).