Bring small sauce pot to medium high heat.
Add olive oil followed by the minced garlic. Stir and sizzle for ~2 minute.
Carefully pour cooking wine into the pot. Be careful of any flames.
Reduce the wine/liquid by half, roughly 2-3 minutes. Turn to low heat.
Stir in mustard followed by incorporating the tarragon. Stir well – it will look more like a mustard pace and not really a “sauce.”
Bring to medium high heat and add both coconut milks. Stir.
Bring to a boil, about 30 seconds. Once it is at a boil, turn to lower heat or to a simmer. Season to taste.
Remove from heat and serve over fish, chicken or protein of choice.