Cut 6 very thin slices from center of each pear (do not core). Chop remainder of pears to measure 1 1/2 cups.
Combine 3 cups sugar and water in a saucepan; bring to a boil, stirring constantly. Add pear slices, and boil, stirring occasionally, 20 minutes. Drain and arrange 8 pear slices on parchment paper-lined baking sheets, overlapping wide edges. Repeat procedure with remaining pear slices.
Bake at 350° for 5 minutes or until edges begin to brown. Let stand overnight.
Beat oil, 1 cup sugar, and egg at medium speed with an electric mixer until blended. Combine flour and next 3 ingredients; gradually add to oil mixture, beating at low speed after each addition. Add chopped pear, pecans, vanilla, and, if desired, coconut; beat at low speed just until blended.
Grease and sugar 6 (6-ounce) custard cups, and spoon batter into cups.
Bake at 325° for 40 minutes or until a wooden pick inserted in center comes out clean. Cool in cups on a wire rack.
Remove cakes from cups, and press a strip of pear slices around sides of each cake. Serve with Praline Sauce, and garnish, if desired.