Steam broccoli until tender, either using a steamer basket or just in a small pan with a little water in the bottom. Drain and let cool until cool enough to handle.
Once cool, add broccoli to a food processor and pulse until chopped into very small pieces, 10 - 15 pulses. Add chickpeas, quinoa and mustard and pulse until a dough starts to form.
Transfer mixture to a bowl, add in remaining ingredients (starting with 4 tablespoons quinoa flour) and knead by hand until dough can be formed into patties, adding more quinoa flour as needed.
Form dough into patties and place on a parchment lined sheet / plate. Chill in fridge for at least 1 hour.
1) Heat oil over medium high heat. To test if it's ready, sprinkle a little water on the pan. If water immediately sizzles, the pan is ready. Add burgers to pan, cooking until browned on both sides, 2 - 3 minutes per side. Place on wire rack to cool while finish cooking.
2) Preheat oven to 350 degrees F. Line a baking sheet with parchment, add patties and bake on the center rack for 20 - 30 minutes, flipping halfway through, until burgers are crispy.