Preheat oven to 400F and line a baking sheet with parchment paper.
In a large mixing bowl, combine oat flour, tapioca flour and coconut flour, baking soda and baking powder. Mix together with a wire whisk.
In a small bowl, whisk eggs and combine with apple cider vinegar, maple syrup, water and extra-virgin olive oil.
Pour wet ingredients into dry ingredients and mix well with wire whisk. Let batter settle for a few minutes so coconut flour absorbs all the liquid. Once mixed use hands to form into a ball and then divide dough into 4 balls. See tips if batter is too sticky.
Form into a bagel by flattening the ball slightly and poking a hole through with your finger (see my video on Cinnamon Raisin Bagels for an example).
Boil a large pot of water (not a rolling/rough boil otherwise bagel can fall apart moving around too much). Add each bagel one by one and let boil for 10-20 seconds or until the bagel rises to the top of the water. Be careful the bagel doesn't get stuck on the bottom of the pot.
Place bagel from water directly on to parchment paper covered baking sheet. Sprinkle 1 tsp of sesame seeds on top of each bagel. Bake for 20-30 minutes or until the bagel is cooked through.