Heat 1 tablespoon olive oil in a medium saucepan. Add fennel seeds, onion and garlic. Sauté on medium heat until onions are caramelized. Remove from heat. Place mixture in a large bowl.
Add quinoa, beetroot, buckwheat flour, dill, mustard, flax meal and salt to the bowl. Mix well. Take about half a cup of the mixture in the palm of your hands and shape into a patty. Repeat with the remaining mixture.
Heat the other tablespoon of olive oil in a large frying pan on medium-low. Gently place the patties in the frying pan. Reduce heat to low and cook for 10-12 minutes. Flip the patties and cook on low for another 10-12 minutes until the patties are golden all over and quite dry to touch.
Remove and serve hot with burger buns, guacamole, shaved cucumbers, sliced onion and hot sauce.
Meal Prep - Burger mixture can be prepped a day or two in advance. Alternatively, raw burger patties can be prepped and stored in the fridge for up to three days before being cooked.Freezing - Cooked patties will keep well in the freezer for up to a month and can be thawed and re-crisped on a pan when ready to use.Scaling - Recipe can be easily doubled.