Some members of the public also expressed their concerns online.
"It's not that they're not food-grade silicone, it's that they haven't been tested with heat.
"They aren't the right thickness to use in the oven.
"They're fine for freezing, but not baking."
Kmart responded to the viral hack saying it should not be used for baking.
"We do not recommend the Giant Ice Cube Tray for use in the oven as it has not been heat tested for this use," an Australian Kmart representative wrote in a letter to a shopper.
When products made out of silicone are used for baking, experts say the product can cause a foul odour.
The Giant Ice Cube Trays are sold here in Kmart's across the country for $2 each.