- Place all ingredients, except vanilla extract, into a saucepan and cook over medium heat, stirring constantly.
- Once the mixture starts to boil continue stirring for 1 minute (until mixture slightly thickens). Remove from heat and add vanilla extract.
- The sauce will slightly thicken as it cools. You can use the sauce right away or place it in an airtight glass jar in the fridge for up to 1 week. The sauce may harden after being in the fridge but just slightly warm it up and give it a stir when ready to use again.