Start by simmering the red lentils in unsalted water according to package directions. This should take about 15 minutes until they’re tender. Drain the lentils and set them aside. Keep an eye on the texture; they should be soft but not mushy.
In a large skillet, heat the olive oil over medium-high heat. Once hot, add in the chopped red bell pepper and finely chopped yellow onion. Sauté this mixture until softened, which should take around 5 to 6 minutes. You’ll notice the onions becoming translucent and the peppers softening.
Next, stir in the matchstick carrots, minced garlic, and peeled and minced fresh ginger into the skillet. Sauté everything for one more minute, allowing the garlic and ginger to release their aromatic flavors. You’ll want to smell that fragrant blend filling the kitchen.
Add the drained lentils to the skillet along with the hoisin sauce, soy sauce, rice vinegar, sesame oil, and water chestnuts. Toss everything together while heating for about one minute, ensuring the lentils are evenly coated. If the mixture appears too thick, you can thin it with a few tablespoons of water. It’s important that the lentils absorb some of the sauces as they rest.
Once combined, fold in the chopped walnuts, and sprinkle with green onions, cilantro, and optional sesame seeds. This adds great texture and flavor to your filling. Make sure everything is well mixed and heated through.
Now it's time to serve! Take the filling and spoon it into the fresh leaves of iceberg lettuce or butter lettuce. I personally like to double up on the lettuce leaves for extra crunch and sturdiness. Enjoy your wraps warm, and feel free to customize with extra toppings if you’d like!