Into a large pot add vegan butter and heat for 30 seconds on medium-high heat. Add your red bell peppers and mushrooms and cook for around 5 minutes or until soft and translucent. Add in your garlic and lentils and cook for 5-7 minutes or until your peppers are soft. To the pot, add the salt, black pepper, oregano, thyme, and sherry vinegar. Stir until the peppers, mushrooms and lentils are well coated and turn heat to low to cook and marry for around 3 minutes. Stir often to avoid burning.
Into the pot add your ground walnuts, ground pecans. Stir the ingredients till combined and cook for 5 minutes.
To the pot, now add the California Prunes, passata and water. Stir, stir, stir, bring to a boil then simmer for 30 minutes until thick and luscious like a traditional meat sauce. Just before removing from heat add in your rainbow chard and cook down just till wilted and soft. Set aside.
Preheat oven to 400F and line a baking sheet with parchment paper.
While your “meat” sauce is simmering prepare your mashed sweet potatoes by boiling water in a large stockpot. Season your water and cook your potatoes till very tender, could take 15 minutes or so. Strain your potatoes but absolutely do not rinse and return to pot. Add the remainder of the ingredients and mash till extremely rich and creamy! Remember, when adding your liquid that you must have a more solid mash to add on top of the first layer! Set aside.
Into a 13″L x 7.75″W x 2.25″H baking dish transfer your “meat mixture” and lay it flat using a spatula. Begin dolloping your mashed potato onto the mixture and using a flat tool flatten it all out. I like using a fork to carve marks vertically and horizontally across the pie. This adds fun texture and when it cooks gets nice and golden brown! Before cooking spray the mashed potatoes with an oil of your choice for that added golden colour (you will thank me later if you do this).
Cook for 25 minutes before setting the oven to broil for 5 minutes. Watch closely so nothing burns but this is an amazing adding touch to the recipe!
If you don't have pecan, then just use 2 cups total of ground walnuts