Add luke warm liquid to gelatin crystal. It may be water, juice or milk. Mix at regular intervals until all crystals completely dissolve, about 2 minutes. No gelatin crystal should be lingering around the vessel or spoon, all should be dissolved.
Runny gelatin desserts may as well just be sugar soup, so first let's cover what you did wrong. Chances are you didn't follow the directions exactly, adding too much water or watery fruit (via Butter With A Side Of Bread). Jell-O also won't set if left on the counter, it needs to chill in your refrigerator.
Saving A Curdled Dish The simplest way to do that is with a starch thickener. Whisk flour or cornstarch into a small saucepan of cold milk and bring it to a simmer. As it thickens, slowly whisk in your salvaged sauce.
Heating and re-heating gelatin Gelatin has a fairly low melting point and will become liquid if left in a warm environment. Small amounts of gelatin can be melted in a container placed in warm tap water. Larger amounts can be re-heated over a pot of boiling water.
When potatoes are mashed, starch is released. The more you work the potatoes, the more starch gets released. When too much starch gets released, the potatoes become gummy, gluey, and unappetizing. We also suggest using a ricer or food mill for fluffy, lump-free mashed potatoes.