The Best Vegan "Pulled Pork" Sandwich!

Name: The Best Vegan "Pulled Pork" Sandwich!
Prep time: 7 min
Cook time: 35 min
Total time: 42 min
Cuisine: American
Ingredients: 2 cups water; 1 cup green lentils ((well rinsed)); 2 Tbsp olive, avocado, or grape seed oil; 1/2 medium white or yellow onion ((minced // plus more for serving)); 1 ½ cups packed finely shredded/grated carrots; 2 Tbsp coconut sugar or organic brown sugar ((plus more to taste)); 1 ½ tsp ground paprika ((we prefer smoked)); 1 tsp garlic powder; 1 healthy pinch each sea salt + black pepper ((plus more to taste)); 3/4 cup vegan BBQ sauce ((plus more for serving // gluten-free as needed // I used Annie’s original BBQ sauce)); 2 Tbsp water; 4 medium gluten-free or whole-wheat hamburger buns*; Finely chopped purple cabbage, carrot, and green onion ((optional))