Steam the cubed orange sweet potatoes for 12 to 15 minutes until fork-tender. Transfer to a bowl and let vent for 5 minutes, then coarsely mash them leaving visible bits.

Simmer the rinsed red lentils in 2 cups of water for 10 to 12 minutes until soft. Drain thoroughly using a fine-mesh sieve and let air-dry for 5 minutes.

Fold the soft red lentils, sweet potatoes, arrowroot powder, ground cumin, smoked paprika, garlic powder, onion powder, and fine sea salt together until a coarse mixture forms. Let rest for 10 minutes, then shape into six thick, round patties.

Heat avocado oil in a cast-iron skillet over medium-high heat. Sear the patties for 4 to 5 minutes per side until a deep golden-brown crispy crust and charred edges form.

Blend the ripe avocados, fresh cilantro leaves, lime juice, water, and sea salt in a high-speed blender until a thick, vibrant green sauce forms.

Stack the seared patties on a ceramic plate. Dollop generously with the thick avocado cilantro sauce, then garnish with chopped fresh cilantro, toasted black sesame seeds, and sea salt flakes.