• Soak cashews in boiling water for at least 30 minutes.

Make Sauce

• Grate garlic. Heat olive oil in small pan, add garlic, salt and pepper and stir, cooking, until fragrant, about 1 minute. Drain cashews and add to blender along with garlic and oil, nutritional yeast and water. Blend until smooth and creamy.

Make Topping

• Place pine nuts, hemp seeds, nutritional yeast, garlic powder and sea salt into spice grinder (or use a coffee grinder or very small food processor/blender. Pulse/grind until well mixed and crumbly, careful not to turn into a pasty mush. Set aside this vegan parmesan cheese.
• Toast one slice of bread. Pulse in small food processor or spice grinder until the texture of breadcrumbs is acheived. Use the same small pan from the sauce, heat 1 tablespoon olive oil and toss the breadcrumbs in it until golden brown.

Assemble Gratin

• Trim and peel parsnips. Use mandolin or slicing disc of food processor to thinly slice (about ⅛") parsnips. Place sliced parsnips along with half the sauce into a large mixing bowl. Continue to mix until all parsnips are thoroughly coated with sauce.
• Arrange half the coated parsnips in casserole dish. Pour on half the remaining sauce. Sprinkle on half the vegan parmesan.
• Add the remaining parsnips, then the remaining sauce and finally the remaining vegan parmesan mixture. Then sprinkle on the toasted bread crumbs.
• Bake in preheated 375 degree oven for 45-50 minutes, until parsnips are tender.