Preheat oven to 300F and line a large rimmed baking sheet with parchment paper.In a food processor, process almonds and pecans until they resemble coarse crumbs with some larger pieces. Transfer to a large bowl and stir in flax seed meal, sunflower seeds and vanilla protein powder.In a small saucepan over low heat, melt peanut butter, butter and erythritol together until smooth. Remove from heat and stir in stevia extract.Pour peanut butter mixture over nut mixture and stir well, tossing lightly. Stir in water. Mixture will clump together.Spread mixture evenly on prepared baking sheet and bake 20 minutes, stirring every 5 minutes or so, until golden and beginning to crisp. Turn off oven and let sit for another 20 minutes or so.