Here's how you do it:
Slice your red and green apples, trying your best to keep them the same size. Place your apples on a larger plate or serving platter.
Melt chocolate and place in a piping bag. Have your child squeeze the chocolate to make the antennas, face, and feet of the caterpillar.
If you own the book, take this opportunity to read it to your child. Have them decide which fruit they would want to try next.
Incorporating characters your children already like is a great way to pique interest in new things. This activity is great for fine motor skills, creativity, and becoming more comfortable with textures (like the squishy melted chocolate).
You can expand on this activity by using other fruits or veggies. Let your child use their imagination to create caterpillars. Incorporate other sauces and flavors into the mix, like ranch, peanut butter, or hummus.