Chocolate bomb is a gnome dish that can be made at level 42 cooking. The premade version is sold in the food shop in the northwest corner of the 1st2nd floor[?] of the Grand Tree for 160 gp, with 3 in stock. It heals 15 hp and can be eaten in the same game tick as another food if clicked immediately after the other food (thus if eaten with a shark, you can heal 35 hp with the same delay eating just 1 shark would produce).
Bake the Half made bowl which removes the Unfinished bowl from the gnomebowl mould (returning it to your inventory).
Use the Unfinished bowl with two pots of cream and one chocolate dust to create the Chocolate Bomb. This grants a final 110 Cooking experience for a grand total of 190 experience for making the Chocolate Bomb.