Erin O'Brien on Instagram: "How to make the perfect Steak Diane at home 🥩🍷 It’s so delicious and easy to make! Hope you love it 💕 Serves: 2 to 4 4 4-ounce beef tenderloin filets Kosher salt, to taste Freshly ground black pepper, to taste 1 tablespoon avocado oil 3 tablespoons unsalted butter (divided) 1 small shallot, finely chopped 2 medium cloves garlic, finely chopped 8-ounces baby bella mushrooms, thinly sliced ¼ cup brandy or cognac 1/3 cup veal demi-glacé ¼ cup creme fraiche 1 teaspoon