Mary Naserian in her kitchen, where she uses an improved cookstove.The morning light filters into Alice Siamanta’s home in Nalepo, Kajiado County, on the outskirts of Nairobi. Her kitchen walls are cleaner, her pots shine, and they have no soot. Her children are busy doing their homework, seated near her. The house is silent, with only the sound of books; there is no coughing. Alice cooks on a clean cookstove purchased through her savings in a women’s savings group.“I never believed cooking could be this easy,” she says, smiling while lifting a pot of simmering beans. “No more tears in…