Mango-lime ice cream spiked with a wee bit of ancho chili powder, I decided, would compliment the New Mexican menu my neighbors had described. More importantly, it offered a real advantage in a time crunch: pectin. Mangoes, having lots of this soluble gelatinous polysaccharide that is used to set jams and jellies, allowed me to skip cooking a custard. Because of the pectin, a richness and weight on the tongue is achieved without eggs. Instead of having to heat milk, temper eggs, cook the custard, then chill it, all I had to do was puree the mango with sugar and lime, stir in the milk and cream, and leave it in the fridge until churning time.