In a large pan, heat grapeseed oil until shimmery.
Add bell pepper, and cook on medium high heat until slightly browned- about 4 minutes
Add eggplant and zucchini, cook until reduced by half- about 10 minutes.
Add walnuts, diced tomatoes, stir well and stir in taco seasoning with water.
Stir well to mix and be sure seasoning evenly coats mixture.
Let water cook off - about 10 minutes.
Heat a large cast iron or nonstick pan on medium high until hot to the touch (sprinkle a little water in the pan to know if it is hot- it will sizzle if it is!)
Reduce heat to low.
Add filling into 1/2 of tortilla, and place filling side up in pan.
Let tortilla soften for about 30 seconds, then fold over.
Cook on low until lightly browned, about four minutes.
Flip and cook on other side until lightly browned.
Remove and serve immediately. Repeat with remaining tortillas.