The unnamed Grandmother is the villainess of The Oven, a short horror film from CryptTV (release date August 18, 2017). She was the grandmother of the film's unnamed protagonist, who woke up in the film's beginning to find himself trapped in an oven.
As the man attempted to call 911 on his cell phone, his grandmother suddenly appeared at the oven door, asking him if he was comfortable. The psychotic woman then told him that it was going to get "a little cozier" in there, ignoring her grandson's pleas to be let out as she turned on the oven. The evil grandmother then walked away, allowing her grandson to be burned alive inside the oven.