Preheat oven to 300* F. In a medium bowl combine flour, soda and coriander with a wire whisk, set aside. In a large bowl cream butter and sugar with an electric mixer at medium speed to form a grainy paste. Add eggs and lemon extract, and beat well. Scrape down sides of bowl. Add the flour mixture and the chocolate chips, and blend at low speed just until combined. Drop dough by teaspoons onto ungreased baking sheets, 4 cm apart. Bake for 14-15 minutes on center rack of oven. Do not brown. Immediately transfer with a spatula to a cool surface.