Use a 1.5 quart sauce pan to melt the butter on medium heat. Saute the shallots until lightly browned and then stir in the blueberries, stirring to coat them in the butter.

Pour in the lemon juice and chicken broth. Reduce the heat and bring to a simmer.

Stir in the lemon zest, fresh thyme, salt, and sage, if using.

Let the sauce simmer until the blueberries fall apart and the sauce thickens, about 15-20 minutes. The pectin in the blueberries will naturally thicken the sauce even as it cools.

Taste for sweetness and add according to your preference.

Sauce can be refrigerated for up to three days or frozen for up to three months.