One of my hobbies is to take words that are not onomatopoeias and say them as if they are. For instance imagine if the word "eat" was not only a word describing the mastication of edible substances but it was the sound you made in doing so. "mmm this is good," eat eat eat eat, "real tasty," eat eat eat. Here is a list of some that come to the top of my head:
Some are harder to imagine than others, like befuddle.