In the bowl of a standing mixer fitted with a dough hook, (or in a large mixing bowl if kneading by hand) put flour, sugar and yeast and mix on low speed for about a minute.
Add the melted butter, vanilla extract, egg, and egg yolk and mix for another minute.
Slowly pour in the water and mix to form the dough. If after 2 to 3 minutes, the dough hasn’t come together and there are pieces of dough at the bottom of the mixer, add a few drops of water.
Increase the speed to medium and add the salt. Let the mixer knead for an additional 4 to 5 minutes. Scrape the bottom and sides of the bowl as needed.
Optional: add raisins or cranberries and knead on low speed for one more minute, just until incorporated.
Transfer the dough from the mixing bowl to a very lightly floured work surface. Finish kneading by hand - stretching, tearing and pushing the dough away from you, folding it back on itself, giving it a quarter turn and repeating. Finally, give it a nice round shape.
Grease the dough with a little bit of oil, cover it with a kitchen towel, place the bowl somewhere warm and let the dough rise until doubled. It can take 1 to 3 hours at room temperature.
Separate the dough into equal pieces and roll each piece of dough into a long rope.
Braid the ropes to your desired shape.
Line a baking sheet with parchment paper and place the Challah on it.
Place the pan somewhere warm, cover it with a towel and let it rise until puffed, about an hour.
Heat the oven to 400°F/200°C. When ready to bake, brush the Challah all over the with the maple syrup.
Slide the Challah on its baking sheet into the oven and bake for 25 to 30 minutes. The Challah is done when it is a rich golden brown and registers 190°F/90°C in the very middle with an instant-read thermometer.
Let the Challah cool on a cooling rack. Enjoy!