Pour popcorn into a large bowl. In a glass or plastic bowl, combine the margarine, brown sugar and marshmallows. Cook at 1 minute intervals in the microwave, stirring between each time, until the mixture is melted and smooth. Stir in the peanut butter until well blended.
Pour the melted mixture over the popcorn, and stir quickly to coat the corn before it cools.
Really easy to make, but not quite sure if it is supposed to go hard, or do you just eat it while it's sticky ? Is it supposed to be served in a clump or separate like ordinary popcorn ? I didn't use all the popcorn because there did not appear to be enough mixture to cover 2 pkts. May be why mine is like really sticky toffee ?. Have pressed it into a tray and put it in the fridge. If it goes hard , will just chop it and serve that way.. We'll see. - 27 Jun 2012