Mince the garlic finely and set aside. Finely chop the onion into about 1/4-inch pieces and dice the red bell peppers into similar-sized pieces. Dice the water chestnuts into 1/2-inch pieces. In a small bowl, whisk together the coconut aminos, rice vinegar, ginger, sesame oil, and arrowroot powder, stirring until the arrowroot is fully dissolved and there are no lumps. This creates a smooth, glossy sauce that will coat the turkey beautifully.

Heat the avocado oil in a large skillet over medium-high heat until shimmering. Add the chopped onions and peppers, cooking for 3-4 minutes, stirring occasionally, until the vegetables are softened and the onions become slightly translucent. This develops a sweet, caramelized base for the turkey. I like to cook the vegetables first because it builds flavor and prevents them from being too crunchy in the final dish.

Increase the heat to medium-high and add the ground turkey to the skillet with the vegetables. Break it apart with a wooden spoon as it cooks, stirring frequently to ensure even browning and to break up any large chunks. Cook for 6-8 minutes until the turkey is no longer pink and has achieved a light golden-brown color throughout. This browning develops deeper, savory flavors in the meat.

Tilt the skillet and carefully pour off any excess liquid that has accumulated in the pan—this removes excess moisture and fat that would dilute the sauce. Add the diced water chestnuts from Step 1 and pour in the sauce mixture, stirring constantly to coat all the turkey and vegetables evenly. The sauce will begin to thicken immediately as the arrowroot powder activates from the heat.

Reduce the heat to medium-low and simmer the turkey mixture for 2-3 minutes, stirring gently, until the sauce thickens and becomes glossy and coats the turkey and vegetables. In the last 30 seconds of cooking, stir in the minced fresh garlic. I add the garlic at the very end to keep it bright and fresh-tasting rather than cooking it down into a muted flavor. The filling should smell fragrant and look well-combined with a light sauce coating everything.

While the filling is still warm, remove it from the heat and arrange the Boston Bibb lettuce leaves on a serving platter. Spoon about 2-3 tablespoons of the warm turkey mixture into the center of each lettuce leaf. The lettuce leaves are naturally pliable and slightly sweet, making them the perfect gluten-free vessel for this savory, umami-rich filling. Serve immediately while warm.