Heat a cast iron skillet over medium heat for about a minute and then add the walnuts.
Turn the heat to low and toast the walnuts, stirring occasionally for 3 minutes. Keep an eye on them to make sure they don't burn.
Place the toasted walnuts along with the basil, garlic, lemon juice, sea salt and water in the food processor and process for several minutes until creamy and smooth.
Make the Mushrooms and assemble your sandwich
Heat a cast iron skillet over medium heat for a minute or so until it's warm.
Add the garlic, shallots and parsley and cook for a couple of minutes, adding 1 tablespoon of water at a time when the mixture starts to stick to the pan. You don't want the pan to be full of water, you want the water to evaporate quickly just to give some moisture to the mixture. This will draw the flavor out of the garlic and the shallots.
After 2 minutes or so, add the mushrooms and the sea salt and another tablespoon of water.
Cook the mushrooms for 4 or 5 minutes, stirring frequently until all the mushrooms are soft.
To assemble, toast some sprouted whole grain bread, spread on a generous amount of pesto, pile on the tomatoes and top with the mushrooms.
Notes
Cut into quarters and serve as an appetizer or finger food at your next camping Scientology party. Who knows, maybe Pink will show up and you can tweet about it. Just don't invite me, I would have no idea where to even start.