When going for deficit, how to aim for daily protein requirement without the help of low calorie protein shakes?

That will need a hell lot of egg whites ...

Current weight : 87kg (body fat estimate at 18-20%)
Height:175cm

Goal: 78kg @ 12% body fat.
Duration : 3 months

Current routine : PLP off PLP off repeat, 90% intensity, 45-60min each session.

Current meal:
Breakfast
- 1/2 cup dry oats
- 150g chicken breast
- 2 whole eggs+ 3 whites only scramble with 1 tbs olive
- 1 whole square tofu
- 1 pcs of black mushroom
- 4 inches of fuchuk
- half packed enoki mushroom
All the above cook like porridge

Lunch/ pre work out
- 2pc wholemeal bread
- 2 whole eggs + 4 whites only

Dinner
- 200g chicken breast steam
- 2 whole eggs + 3 whites scramble with 1 tbs olive oil
- 1 whole square tofu
- one cup mix veges( brocolly/ carrots/ greens/ mushroom ), steamed, mix with 1tbs of oyster sauce.

I had been eating mostly the same for the past 4 months and had been losing 15-16 kg from 102-103kg after dirty bulk cycle.

Currently the weight loss started to get really slow. Shoud I tweak my food?[attachmentid=6254978]