Remove the soaking mushrooms from the water but don't throw the water out. We will use it in the sauce. Chop up the porcini mushrooms to fine pieces.
Add the frying pan back to the burner over medium high heat. Add the remaining 2 tablespoons of olive oil and let it get hot. Add the crushed garlic, chopped anchovy fillets and chopped up porcini mushrooms.
When those ingredients start to sizzle, add the white wine, lemon juice and the water the porcini mushrooms soaked in. I used a funnel lined with a paper towel to remove any sediment from the water. I would have liked to use a coffee filter in a funnel but couldn't find any.
Add the thyme sprigs and season with a little salt. Bring the sauce to a low boil and cook until it is reduced by half.