Dice the rhubarb and add to a small saucepan over low heat. Add ½ a tablespoon of water. Stir occasionally as they heat up and start releasing their juices.

Once much liquid has been released, turn the heat to medium. Let them simmer, constantly stirring until their liquid has reduced by at least half and the mixture has thickened. Pour the rhubarb and remaining liquid into a bowl and let it cool down until just warm.

Combine water, yeast, and sugar in a large bowl or the bowl of your stand mixer fitted with a dough hook. If using active dry yeast, let this sit for around 5-10 minutes until it becomes foamy, if using instant yeast, this step can be skipped

Add the flour, vanilla, salt, cinnamon and rhubarb mixture.

Use a fork or switch the stand mixer to low speed to combine into a thick dough. The dough should be very thick but also slightly sticky dough. If it's too sticky, add a little flour. If it's too dry, add a tablespoon of water. It will all depend on how much water was reduced in the rhubarb.

Knead or mix for about 8-10 minutes until smooth.

Form the dough into a ball, place it in a large bowl, and cover it with plastic wrap or a damp towel. Let the dough rise in a warm place until doubled in size.

Punch down the dough and transfer it to a lightly floured surface. Cut the dough into 8 equal pieces and shape each into a ball. Let the dough balls rest for 5 minutes, then use your thumb and index finger to create a hole in the center of each ball. Widen the hole by rolling the dough circularly around your fingers.

Place the shaped bagels on a prepared sheet pan lined with parchment paper and let them puff out for around 30 minutes while the oven preheats and a pot of water is brought to a boil.

Bring a large pot of water to a boil and preheat the oven to 428°F/220°C. Line a baking sheet with parchment paper. Stir honey or brown sugar into the boiling water.

Poach the bagels for 1 minute, flipping after 30 seconds. Remove the bagels with a slotted spoon and let them drain. Place them on the prepared baking sheet.

Bake them in the oven for 15 minutes on the center oven rack until they turn a deep golden brown. If they're baking unevenly or your oven has hot spots, rotate the baking sheet after 7 minutes.

Remove the bagels from the tray and let them cool on a cooling rack for 30 minutes before slicing and serving.