Make the purple rice first, mix the regular white sushi rice with black forbidden rice at a 4:1 ratio, and add 10 minutes to the white rice program on your rice cooker;
Slice the tofu into 1/2 inch thick pieces, mix together all the glaze ingredients;
In a nonstick pan, heat a drizzle of oil over medium-high heat, pan fry the tofu until both sizes are golden crispy, about 3-4 minutes for the first side and another 2-3 minutes for the other size;
Once the tofu pieces are all golden brown, give the glaze another stir in case the arrowroot powder has settled at the bottom, slowly pour the sauce into the pan;
Lower the heat immediately, swirl the pan around and flip the tofu pieces to coat them all evenly in the glaze;
Once the glaze is thickened and "glued" onto the tofu, remove from heat;
When ready to assemble the onigirazu, place one piece of nori onto your work surface, make a cut from the middle point of one edge to the center of the nori sheet;
Press down some purple rice on a quarter of the nori, drizzle on some homemade vegan mayo, then a few tofu pieces to the next quarter;
Then some lettuce and cucumber, finally the avocado slices and your favorite chips on the last quarter;
Start folding where the cut is, fold one quarter onto the next one, until it become one thick square;
Cut in half diagonally, enjoy!