The oven has 4 initial slots for preparing meal instead of six, as other crafting stations. However, these 6 slots are there to begin with, but for some reason the oven recognises only 4. I can still use all 6 slots, but I need to wait for first item to be done to actually queue a 5th item. I also need to wait for second item to be done crafting to queue 6th slot. If I try to use shift to batch queue crafting, it will give me a 'no ingredients' error.