Add 8 drops of red food coloring to peanut butter.
Slice off the sides of the apple leaving a 1″ section in the middle which includes the core.
Slice each of the sides in half and then cut out a wedge in each to make a mouth. Tip: If you are making these up in advance, use lemon juice on cut areas of apple to minimize browning.
Fill apple mouth with dyed peanut butter.
If using mini marshmallows: allow them to sit open on a counter for several hours to begin to dry out, so they are easier to cut. Then use scissors and cut diagonally to shape fangs or horizontally to make teeth.
If using sliced almonds: Use a knife to trim almond slices if you want a nice straight edge for teeth.
If using yogurt covered raisins: place as desired. If your apples are small, only one row of teeth will fit.