Peel the oranges, careful to get only the outer peel and not the bitter white pith below.

Cut the oranges in half and juice them into the pan.

Combine sugar, water, orange juice, and lemon juice in a small pot. 

Bring to a simmer over medium heat, stirring until the sugar has dissolved. 

Add in the orange peels. 

Remove from heat and allow the mixture to cool for 30 minutes.  

Strain syrup through a fine mesh strainer to remove the orange peels and any pulp from the juice. Stir in food coloring. 

Pour into a glass, airtight container (like a mason jar or glass bottle) with a lid. 

Store your blue curaçao syrup in the refrigerator for up to 3 weeks.