Cook the Pasta: Start by boiling a large pot of salted water until it reaches a rolling boil. Add the uncooked pasta and cook according to package directions until it reaches al dente perfection, usually about 8-10 minutes.

Sauté the Mushrooms and Garlic: In a skillet over medium-high heat, melt the butter and olive oil together until shimmering. Add in the sliced cremini mushrooms along with minced garlic, sautéing them for about 5 minutes until they release their moisture and become tender.

Prepare the Sauce Base: Once the mushrooms are cooked, remove them from the pan and set aside on a plate. In the same skillet, add dry white grape juice, Italian seasoning, lemon juice, flour, and Dijon mustard; stir them together until they form a smooth paste without lumps.

Create the Creamy Mixture: Gradually pour in heavy cream while stirring continuously to combine all elements smoothly. Allow it to simmer gently over low heat for just a couple of minutes until it thickens slightly.

Combine Everything Together: Return the sautéed mushrooms back into your creamy mixture and let them mingle on low heat for another few minutes while seasoning with salt and pepper to taste.

Toss with Pasta and Serve: Drain your cooked pasta and immediately toss it in with the creamy mushroom sauce along with freshly chopped parsley and grated parmesan if desired before serving hot!