Combine the butter or margarine, syrup, brown sugar, cocoa and vanilla flavouring in a medium saucepan.  Stir continually on medium heat until it starts to boil with bubbles all over the surface.  Remove from heat and place on a hot pad.

Put the measured puffed wheat into a very large bowl.  Pour the chocolate mixture over the top.  Use a rubber spatula to scrape all the mixture out of the saucepan.  Stir well until all the puffed wheat is coated.  Grease a 9″ x 9″ pan.  Turn the coated puffed wheat into the pan.  Press down firmly using the dampened spatula.  Chill for about 2 hours so it will cut cleanly.

Cut into 16 – 25 squares.

Substitute: Crustal or other plant-based (non-dairy) margarine for butter to make this recipe non-dairy.