Pretty and Polished: Slimming World Brownies. Works out as syns in total for the whole tin (including the icing). So you would just need to cut them into however many squares you like and work out the individual portion's syn value.
Conversion chart for substituting greek yogurt for butter. ~ been trying to find a substitute for cooking with nasty who-knows-what's-in-it margarine . but butter does exactly that . Gonna have to try the greek yogurt idea.