Heat olive oil in large frying pan over a medium heat and add turkey steaks. Cook for 5 minutes then flip and add the garlic and mushrooms to the frying pan.
While the turkey is cooking, make the basil sauce. In a small saucepan, melt the butter then add the flour and stir. Add the milk a little at a time to form a roux - don't stop stirring. Once the sauce thickens, season with salt and pepper and stir in the pesto and grated cheese.
Serve the turkey and mushrooms over a bed of wild rice and spoon the sauce on top.