crunch — to crush or grind something noisily between the teeth or under the feet

a person takes a big spoonful of crispy cereal and bites down hard with their mouth open. The cereal pieces visibly break apart between their teeth making obvious crushing motions. Small cereal fragments scatter slightly as the pieces get ground up noisily. The person's jaw muscles show the effort of the crushing action. A family member nearby looks over at the loud eating sounds. Another person at the table pauses their own breakfast to notice the noisy chewing. crushing and grinding something noisily between the teeth