To a food processor, puree the hemp hearts, walnuts, basil, and garlic until the walnuts are finely ground. Then add the avocado, lemon, eggs and pulse until combined, then add in the olive oil just until it is thin enough for a sauce. Season with a tiny bit of salt and pepper, if desired (can omit for young babies).
Toss with cooked pasta and serve as is or with cherry tomatoes, and basil on top.
Try to serve this avocado pasta as soon as possible as avocado does go brown over time due to oxidation. The lemon added to the pesto should help slow the processor but it's best to eat it ASAP.
If you're out of walnuts, pinenuts work as well for the pesto but they won't have the same nutritional values as the walnuts.