1Heat oven to 350°F. Grease two 9-inch square pans and two 15x10x1-inch rectangular pans. In large bowl, mix brown sugar, shortening and molasses until well blended. Stir in cold water. Stir in flour, baking soda, ginger, salt, allspice, cloves and cinnamon until well blended. Divide dough into 3 equal pieces. Press 1 piece in each rectangular pan. Divide remaining piece of dough in half; press in square pans.
2Bake one rectangular pan at a time, then both squares together, about 15 minutes or until no indentation remains when touched in center. Cool 5 minutes; turn each pan upside down onto large cutting surface. Cut off any rough edges. Immediately cut 1 rectangle into back and front pieces (including holes for windows and door), and cut other rectangle in half for side pieces (as shown). Cut 1 square into trim and shutters (as shown); cut extra square into gingerbread people, or save for another use. Cool completely, about 25 minutes.
3In medium bowl, beat all frosting ingredients except food colors until smooth enough to spread, beating in additional milk if necessary. Leave most of frosting white; remove and tint small amounts of frosting with food colors for decorating front of house
4Cover cardboard or serving platter with foil. Use frosting to stand front piece of house on cardboard. Attach 1 side to front, then 1 back to side, using frosting. Attach back pieces together at center with frosting. Attach remaining side to house. Attach trim along roof of house; attach door and shutters to door and window openings, using frosting. Fill any gaps with frosting and small gingerbread pieces if desired. Decorate house using remaining frosting, jelly beans, pretzel rods and assorted candies, as desired.