Open a can of full-fat coconut milk and pour a small amount (about ¼ cup) into a large skillet or dutch oven. Add the onion and sauté until very fragrant and softened, about 5 to 8 minutes.
Add the bell pepper and sauté an additional 2 minutes to soften.
Add the remaining coconut milk, panang curry paste, peanut butter, coconut sugar, fish sauce, and sea salt and bring mixture to a full boil.
Reduce heat to a simmer and cook 15 minutes to allow flavors to develop, stirring occasionally.
While sautéing the onion and bell pepper, heat a separate skillet over medium-high and add about a tablespoon of coconut oil. Add the chopped chicken and brown on two sides, about 3 to 5 minutes.
Cover this skillet and continue cooking until chicken is cooked through, about 3 to 5 minutes. Drain any excess liquid off of the chicken.
Transfer the chicken to the skillet/pot with the curry mixture. Continue cooking at a gentle simmer for an additional 10 minutes to allow flavors to come together.
Serve panang curry with your choice of rice, cauliflower rice, zucchini noodles, quinoa, etc.
