I'm working on a raspberry pie recipe, and today was the first pass. I was happy with the flavor, but ran into an issue: it was very liquidy and runny. I used 1/4 cup of cornstarch (for 5 cups of berries). I'm wondering now if I should simply add more cornstarch (and if so, how much more), or if I should use another thickener, like xanthan gum (again, how much?). Does anyone have an opinion on this? Of course I want the pie to be juicy, but it does need to hold together at least a bit when sliced into!