Creamy Champagne Chicken

Bahan-bahan (4 porsi)

• 1 tablespoon olive oil
• 2 skinless boneless chicken breast fillets (halved horizontally to make four fillets)
• 1 pinch salt (to season)
• 14 ounces mushrooms (sliced)
• 2 teaspoons butter
• 1 french shallot (large, finely chopped - normal shallot for U.S readers)
• 1/2 cup champagne (or sparkling white wine)
• 2/3 cup milk (or heavy / thickened cream)
• 1 teaspoon cornstarch (corn flour - only if using milk)
• 1 pinch fresh parsley (to garnish)