Preheat your oven to 350°F and line a small rectangular baking dish with parchment paper for easy removal.
In a medium mixing bowl, whisk together the lupin flour, hemp hearts, chopped almonds, pumpkin seeds, nutritional yeast, chia seeds, sea salt, garlic powder, and black pepper until well combined.
Pour the water into the dry mixture and stir vigorously with a spatula until a thick, sticky dough forms and all the flour is fully hydrated.
Transfer the dough to the prepared baking dish and press it down firmly into an even layer about half an inch thick using the back of a spoon.
Bake for 22 to 25 minutes until the edges are noticeably golden brown and the center feels firm when lightly pressed.
Remove from the oven and let the bars cool completely in the pan to allow them to set before slicing into four equal rectangular bars.