Place a deep, shallow pan over a medium-high heat and add the oil. 

Fry the onion for about 5 minutes, until soft. 

Add the garlic and mushrooms and cook for another 5 minutes, until the mushrooms are golden and the liquid has been released from them and cooked off. 

Add the Castle MacLellan Oven Roasted Mushroom Pâté and water and stir through to create a rich creamy sauce. Simmer for 2 minutes. 

Add the tarragon and simmer for 1 minute.   

Serve with wild rice or mixed grains.