Heat the olive oil in a large deep skillet over medium heat.

Add the diced onion and cook until it starts to soften. Add the mushrooms and cook until tender.

Stir in the diced garlic, then add the ground turkey. Cook, breaking it apart, until no longer pink.

Pour in the beef stock and stir in the onion soup mix. Mix well.

Add the uncooked long grain rice and stir to combine.

Bring to a gentle simmer, cover, and cook on low for 18 to 22 minutes, or until the rice is tender and most of the liquid is absorbed.

Stir the casserole, then sprinkle the shredded cheese over the top.

Cover briefly until the cheese melts, then serve hot.