Whisk the tamari, hoisin, fish sauce, sambal and brown sugar together in a small bowl; set aside. This is your sauce — taste and increase sambal if you prefer more heat.
Heat a large nonstick skillet or wok over medium-high heat until hot, then add the oil. When the oil shimmers, add the diced onion and bell pepper and stir-fry for 2–3 minutes until they begin to soften.
Add the minced garlic and cook briefly, about 20–30 seconds, until fragrant. Push the vegetables to the edges of the pan, add the ground chicken to the center, and let it sear without disturbing for 1–2 minutes to develop color.
Break the chicken into bite-sized pieces with a spatula and continue to cook, stirring occasionally, for another 3–4 minutes until mostly cooked through and any liquid has evaporated.
Pour the prepared sauce over the chicken and toss everything together. If the pan looks dry, splash in 1–2 tablespoons of water to help distribute the sauce. Simmer for 1–2 minutes until the sauce clings to the meat and thickens slightly.
Remove the skillet from the heat, add the lime juice, then fold the basil leaves into the hot mixture — stir just until the basil wilts (30–45 seconds). Taste and adjust seasoning with an extra teaspoon of tamari or a pinch of sugar if needed.
Let the dish rest in the pan off the heat for 1 minute to let flavors meld. Serve over warm jasmine rice and finish with a fried egg, sliced green onions and sesame seeds if using.