I'm not sure if your comment is completely "tongue in cheek", but to "knock up" is a multipurpose phrase in aussie, so it has the same meaning as for you but also several others. Like "fuck"

@Cyklone The difference between implications of the phrase is quite serious.

The subsequent advice is, yes, very much tongue in cheek.

@Cyklone For you folk from the 'Big Smoke' and elsewhere around the planet, the term 'knock up' I used was from the days when I worked as a Shearers Cook.
Shearers NEVER asked what was being made for their meals, they simply asked the Cook what he was '[knocking up," since there were 4 'gradings' of Shearers Cooks back then,

1. The Bait-layer - food was bloody near inedible most of the time,
2. The Pot Rattler, makes a whole lot of noise in the kitchen but the food produced is somewhat edible IF you're hungry enough,
3. The Knock Up Specialist, could even turn a few cans of Baked Beans, Sausages and Mashed potatoes into a Banquet when required, and then there's worst of ALL,
4. The 'Magician,' known to be able to turn good decent food into shit every time.

@Triphid I'm a country boy, mate.

@Cyklone Yep me too, born, bred and raised in the outback, worked 3 seasons straight as a Shearers Cook from the age of 17.
Got 'promoted' to Cook after being Kitchen Rouse-about on my season after it was discovered exactly how the Cook was making rissoles even though he only had one arm.