Step 1

Add the sugar and water to a tall pot over medium heat. Stir gently until all the sugar is wet, then leave it to boil.

Step 2

Reduce the heat to simmer and let it cook, stirring occasionally until the sugar dissolves.

Step 3

Carefully add the chopped rhubarb and stir until it's well coated in the simple syrup.

Step 4

Simmer until the rhubarb is soft, stirring occasionally.

Step 5

Remove the pot from heat and mix in cinnamon, if using.

Step 6

Allow to cool for at least 10 minutes.

Step 7

Serve warm or chilled.