I made these sugar-free bluberry cupcakes for a friend's birthday recently. The recipe called for the usual ingredients as well as the sugar substitute, Splenda. The mixing process was pretty much the same as any other except instead of beating butter & sugar together, you beat the butter & splenda. I coated the blueberries in flour before stirring them into the cake batter so that they wouldn't fall to the bottom while baking. That method worked really well.
When they came out of the oven, they were more scone/biscuit-like instead of regular cupcakes which was just fine with me because it looked just like the picture from the recipe and tasted great too. To keep with sugar-free theme, I topped each cupcake with a dallop of fat-free yogurt and a blueberry. I will try this recipe again using other fruit and maybe less Splenda.