Wash the raspberries thoroughly under running water to remove any dirt or debris. Pat them dry gently using a clean kitchen towel or paper towel.

• a Carefully pick out any stems or leaves that may still be attached to the raspberries.
• b Set aside the cleaned raspberries for later use.

In a large saucepan, combine the water and sugar. Stir well until the sugar is fully dissolved in the water.

• a Place the saucepan over medium heat and bring the mixture to a gentle boil.
• b Reduce the heat to low and let it simmer for about 5 minutes, allowing the flavors to meld together.

Add the cleaned raspberries to the saucepan with the sugar-water mixture.

• a Stir gently to combine the raspberries with the syrup.
• b Allow the mixture to simmer on low heat for approximately 15 minutes, or until the raspberries have softened and released their juices.

In a small bowl, mix the orange juice and corn starch until it forms a smooth paste.

• a Gradually add the orange juice and corn starch mixture to the saucepan while stirring continuously.
• b Cook the syrup for an additional 5 minutes on low heat to thicken the mixture.

Remove the saucepan from the heat and let the black raspberry syrup cool slightly.

• a Use a fine-mesh strainer or cheesecloth to strain the syrup and remove any seeds or solids, if desired.
• b Transfer the strained syrup into a clean and dry container.

Allow the black raspberry syrup to cool completely at room temperature before covering it.