Registering isn't solely about how much profit you make. It just depends on how concerned you might be about getting caught.
Are you claiming this income on your taxes as you ought to be? "Pretty steady business" implies that you are profiting and of course we all
know the government wants a cut of that, no matter how small.
The other factor is that food that is sold should
be prepared and stored in proper conditions as per your local health inspector's recommendations to not only protect your goods, but your customer...and even yourself from lawsuits.
There may also be lax rules in a more rural/cottage area, so you may not have to worry at all about all the regulations like having a separate entrance, doored kitchen, separate bathroom, triple-sink, etc. (Not at ALL to suggest that these places are less clean!! They just allow for things like country market sales, booths by the side of roads, etc. too) Every municipality has its own rules as to whether they care or not. Some forbid food production in places other than strictly inspected facilities, some won't "zone" your home for it, others couldn't care less and MOST don't even know what their own rules are! (You'll see a ton of confusion everywhere about this....one city hall department saying one thing, another department saying another thing. This happens all over!
I know it's a hassle to not only nail down exactly what regulations your area will ask of you and to then comply with some of those if you're doing it from home....but I've heard the fines are pretty stiff.
All it takes is one "competitor" or bad customer to end things for you in a pretty messy, costly and ugly way.
Why not just inquire with the city? Can't hurt to be informed. You might just be surprised to find out that nothing is required of you...then you can sleep better knowing you're doing nothing "wrong" and your business is safe.
All that being said, in the 9 years I've had my own company, I've only heard rumours of one or two people being investigated and inspected and subsequently receiving a fine. I can tell you from having countless friends who make cakes or do catering on the side, it's NOT the health inspector you have to worry about....it's the tax man that is way more likely to catch you.