Preheat your oven to 350F. Use a nonstick rimmed baking sheet or line a baking sheet with parchment.
In a medium mixing bowl or a Pyrex liquid measuring cup, whisk together the syrup, almond or sunflower butter, and vanilla.
In a large mixing bowl, combine the buckwheat groats, flax or chia meal, cocoa powder, salt, pumpkin or sunflower seeds, and almonds. Pour the syrup and nut butter mixture over these dry ingredients. Mix well to combine. The buckwheat granola will be moistened but not wet and forming some clusters.
Transfer the buckwheat mixture to your baking sheet. Spread it evenly, taking care to preserve some of the nice clusters and allowing it to clump together in some places on the sheet.
Bake the buckwheat for 25 minutes, or until the clusters and loose buckwheat groats are evenly toasted. Do not stir during baking—this will help clusters to form.
Remove the baking sheet from the oven and allow the cocoa buckwheat granola to cool completely before using. It can be stored in an airtight container in a cool, dry place for up to 2 weeks.
To prepare the açaí bowls, blend the bananas, açaí, coconut water, chia seeds, and hemp seeds together till smooth. Divide the mixture (it should be nice and thick) into two serving bowls. Top each bowl with any toppings you like, as well as a nice, generous handful of the buckwheat cocoa clusters clusters. Serve right away.