Line a cookie sheet with parchment paper and have your toothpicks handy.
Set out a small to medium bowl of water and add the lemon juice in it.
Melt the chocolate chips in a small slow cooker or microwave them, 1 minute at a time, stirring between each minute until fully melted.
Using a melon baller, scoop the balls out of your ripe pairs. Put the balls in the lemon water temporarily to keep them from browning.
When you are ready to dip them in chocolate, place them on a paper towel to remove most of the water first.
Using a toothpick, pick up one ball, roll in the chocolate and then sprinkle some crushed walnuts over the chocolate while it's still warm.
Set the ball on a parchment lined cookie sheet, leaving the toothpick in the ball.
After dipping all of the pear balls, place the entire cookie sheet in the fridge until the chocolate is hard and you are ready to serve them (at least an hour).
Notes
Please note that the nutrition data is a ballpark figure. Exact data is not possible.