Brew up

From world war two and used, usually by British soldiers, to describe the effect seen when the amunition propellant in a destroyed tank starts to ignite. The flames shoot out of any opening, most usually the turret hatches, extremely violently, like a Roman candle. This terrified tankers and as a sort of black humour they referred to it as brewing up.

Other nationalities sometimes referred to it as cooking off .. the ammunition was cooking off.

The tank was hit with an AP round and within seconds began to brew up.

Brew up

To make a pot of tea. Usually used in the context of plural .. a pot of tea of several cups, rather than single cup, when you would instead say, "making a brew"

I'm just going to brew up. Fancy one?