If you’ve cleaned your sink and it still smells like something died in there, your garbage disposal is the most likely culprit. While your disposal is off, dump a cup or two of ice into it. Then turn on the water and run the disposal. This should dislodge gunk that has stuck to the blades. After the ice has disintegrated, turn the disposal back off and turn off the water. Then dump half a cup of baking soda into the disposal and follow with a cup of vinegar. You should absolutely get the “science project effect,” but that pop and fizz will help clear out any remaining particulates in the disposal. Finally, after the science project has been washed down the drain by some nice hot water, grind a cut-up citrus fruit down the disposal (if you want to eat the fruit, even just the rind will do). The citrus acidity will chew away anything that dared remain, but the real upside is how nice a smell-turnaround your disposal will have made!