If you did not purchase pre-sliced mushrooms, go ahead and slice them thickly.
Thickly slice the shallot and give the garlic clove a rough smash, but try to keep it intact.
Remove the peel from the garlic.
Grate the parmesan using a microplane or a box grater.
Melt the butter in a nonstick pot or pan.
Add the sliced shallot and smashed garlic and sizzle over medium heat.
Once softened, remove about half of the shallots and the garlic clove.
Add the mushrooms into the pot or pan, then reduce the heat slightly and cover the pot with a lid.
Let the mushrooms cook down for about 5-10 minutes, until soft and surrounded by brown liquid.
Add cream and parmesan and stir until combined. Add salt.
Let simmer until slightly thickened.
Optional: add truffle oil to taste.
Serve hot and mixed with or atop of pasta.