ᐅ Plaster broken off – what should be considered when replastering?

Hi everyone, we had a recess cut into the living room wall where we attached a folding structure to hold the projector. Overall, it’s pretty cool.

The problem is that the screws for the hinge ended up right between the masonry and the plaster in the "floor" of the recess, which caused the plaster to break off.

Now I want to replaster it. There is missing plaster about 10cm (4 inches) wide and up to 15mm (0.6 inches) thick.

I still have some Hagalith FF adhesion plaster left over – a bricklayer used it when the wall was done. I’d prefer not to call him back for this small gap.

I’m thinking of thoroughly cleaning the area first, then applying a bonding primer? After that, doing several layers, for example, first 1cm (0.4 inches), letting it dry, then 5mm (0.2 inches), then a finishing plaster? All layers using the Hagalith?

I’d be very grateful for any tips 🙂