Cheese

Cheese is a dairy product that makes occasional appearances in the Mario series. It first appears in Luigi's Mansion. Luigi can scan cheese with the Game Boy Horror to reveal a Gold Mouse, which he can suck up to get treasure. Cheese later appears in Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey, where it can be eaten by Bowser to restore BP, partially replacing Syrup Jars from the previous game.

Mario Kart: Super Circuit
A course named Cheese Land appears in Mario Kart: Super Circuit, which as its name indicates, is greatly themed around cheese, with several cheese structures appearing in the background and off-road areas of the course. The course's moon-like setting which is removed in its later appearance may be a reference to the that the moon is made of cheese.

Mario Kart 8 / Mario Kart 8 Deluxe
returns in Mario Kart 8 and its Nintendo Switch port as a classic course. There are now small blocks of cheese in the off-road areas that act as minor breakable obstacles, and there are now several large cheese blocks in the off-road areas that can block the player.

Luigi's Mansion
In Luigi's Mansion and the remake, Luigi can scan cheese with the Game Boy Horror's Search Function to reveal a Gold Mouse, which he can suck up to get treasure, including jewels.

Five pieces of cheese appear in the game. They are found in the following locations:
 * Study - Behind the desk
 * Fortune-teller's Room - Behind Madame Clairvoya's chair
 * Dining Room - Under the chair next to Mr. Luggs
 * Tea Room - Behind the left table
 * Safari Room - Between the crates and the armchair

Cheese only appears in darkened rooms, and disappears when the room is lit up. However, unlike with Speedy Spirits, Luigi gets a second chance to catch the Gold Mice he missed, during the Blackout.

In Neville's Study, there is a book called Darkness is Their Cheese by C. Parmesan that talks about the effects of cheese in the dark on Golden Mice:

Ghost mice are drawn to darkness as real mice are drawn to cheese... In the dark, they shine gold with contentment. I must try to get close to one before the lights come back on.

Super Mario Odyssey
In Super Mario Odyssey, blocks of cheese called Cheese Rocks appear throughout the Luncheon Kingdom as platforms and obstacles. They can be broken via the frying pans thrown by Hammer Bros, and are sometimes used to cover up various items such as Golden Turnips, Lever Switches, and Moon Shards. They are also used to block some stairs near the Path to the Meat Plateau, which are used in the Under the Cheese Rocks mission.

Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey
In the Nintendo 3DS remake of Mario & Luigi: Bowser's Inside Story, Bowser uses cheese to restore BP instead of Syrup Jars. They recover fifteen Brawl Points when eaten. There are stronger variants of regular cheese: Super Cheese, Ultra Cheese, and Miracle Cheese. Also, Bowser's equivalent of the Star Candy is the Cheesy Drumstick.