Add the olive oil to a small saucepan
Heat the oil over a medium heat. Once the oil is hot add the onion and season with salt and pepper.
Cook the onion for 5 minutes or until tender.
Stir in the corn flour, cranberry juice, orange zest, orange juice, mustard, thyme, port and cranberries.
Stir the sauce well and bring to the boil.
Once the sauce is boiling reduce the heat to low and simmer for 10 minutes or until thickened.
Once thickened remove from the heat and set aside to cool.