If you're making creme fraiche, give yourself at least a day, preferably two.
serves 3-4

1 tablespoon butter
1 tablespoon olive oil
4 shallots, peeled and thinly sliced
1 tablespoon balsamic vinegar
salt for pasta water
2 cloves garlic
1 anchovy (packed in salt or oil but for this dish I love the salty ones)
3 ears corn, shucked and cut off the cob
2 cups mushrooms (use any kind,  but I've been loving the combination of shiitake and hen of the woods ), wiped clean with a wet paper towel and sliced thinly
1 pound pasta
1/3 cup chopped parsley
parmesan cheese
1 cup creme fraiche
coarse salt

Crank a pan to high heat. Add butter and olive oil. Once it's smoking hot, toss in the shallots. Stir for a few minutes until they've softened and browned a bit. Add big pinch of salt and balsamic. Turn heat to low and leave for about 20 minutes. Stir occasionally. 

Boil a big pot of water for pasta. Add a handful of salt.

Bash garlic and anchovy with a mortar and pestle or chop finely. Once shallots are melt-in-your-mouth tasty crispy, add garlic/anchovy puree. Stir and integrate for a minute. Turn the heat back up and add the mushrooms. Toss for two minutes over high heat. They will start to release some water. Add corn. Turn to low.

Place pasta in boiling water. Once the pasta is al dente, add it and a bit of pasta water to the mushroom and corn mixture. Toss. Reduce the sauce down a bit. Add chopped parsley and about 1/2 of the creme fraiche and stir. Taste. Add salt as needed.

Slide into a bowl. Top with paper-thin wisps of parmesan and more creme fraiche. Maybe add more parsley and some coarse salt. Eat right away.