When you call the elevator down, in the freezer room, and the chef is already inside the elevator, you can trick him using the slide, and get inside the elevator fast ... but ... the chef doesn't always start the chase right away. Here's a way to get the Instant chase immediately after the elevator opens:

• position yourself at the left side of the door (of the elevator) facing the foreground;
• make sure you have full stamina, stand still and hold the sprint button;
• go towards the foreground (down) a couple of steps when the elevator door is about to open;
• change direction towards the right as the chef exits the elevator;
• slide towards the upper-right under his arms, when the chef is about to grab you;
• quickly jump inside the elevator before the chef has a chance to reenter the elevator.

NOTE: this STRAT works on the similar elevator-chef chase in the Guests chapter too .. the differences are: you have to position yourself more on the left of the door frame, so the chef doesn't instantly grab you .. AND you don't start to run right way, wait for the chef to look at you stunned, then start running towards the foreground (doing a similar movement as explained above)

here's the latest strat for the elevator chef in Chapter 4 The Guest Area :