A Slim Margarine

My mom has always refused to buy us the following:
Beer.
Cigarettes.
Video games.
Butter.
Real butter. From the churn.
Because why would anyone buy butter at 5 bucks a cube?
Margarine is dollars less than that.
My mother did however, buy me blocks of margarine once.
Hoping that she would trick me into thinking it was butter.
I figured it out, though.
My mother didn't account for my keen taste buds.
And my ability to read.
In cube form the margarine was rock-hard.
So, what I used to do was I'd get my toast going.
I'd chisel some block margarine onto my knife.
Then I'd stick the knife into the toaster while it was toasting.
That way, the margarine would be soft by the time the toast was done.
I stopped doing this, however, when I realized that I was jamming a knife into a toaster.