BAM make an oven cleaner:
It’s a pretty good oven cleaner, but there’s something it’s better at – a laundry prewash or spot cleaner for oily or fatty stains, whether it be cooking oil or engine oil.
The reason it works so well is that unlike the noncaustic Mr Muscle oven cleaner, it comes out as a fine spray. It can be worked into the stain and rinsed out, or simply sprayed on and used as a prewsh. But wait at least 10 min to allow it to react before washing it. Let the chemical do the work.