Rinse the dried lentils and place in a saucepan with the water. Bring to a simmer, cover and cook on super-low heat until soft and tender, about 15 minutes, adding more water as needed to keep the lentils from sticking to the pan. You should have about 2 ½ cups cooked lentils.
With the motor of the food processor running, mince the garlic by dropping it through the feed tube. Add the cooked lentils. Pulse off and on for about a minute, stopping to scrape the puree from the corners. Add the lemon juice, tahini and salt. Pulse another minute or so, them puree until the mixture is creamy smooth. Add warm water, a tablespoon at a time, to thin the hummus as you wish. Taste, and adjust with more lemon juice or salt, if needed.
Transfer to a bowl. Draw an indent in the hummus with a spoon, fill it with olive oil, and a drizzle of sesame oil, if using. Decorate with black sesame seeds, and something green, like cilantro or green onions.
Serve with crackers or baked pita triangles.