Combine the warm water, sugar and salt in the bowl of a stand mixer and sprinkle the yeast on top. Allow it to sit for about 5 minutes.
Add the flour and butter and using the dough hook attachment, mix on low speed until well combined.
Change to medium speed and knead about 5 minutes until the dough is smooth and pulls away from the side of the bowl.
Remove the dough from the bowl, and place the dough in a glass bowl oiled with vegetable oil. Cover with plastic wrap and let rise in a warm place for approximately 50 to 55 minutes or until the dough has doubled in size.
Take a chunk of dough about the size of a ping pong ball and roll into an oval shape. Repeat with remaining dough.
Preheat the oven to 450°F. Fill a large saucepan with water. Bring the water to a boil and add the baking soda.
Place the pretzels into the boiling water for 30 seconds, a few at a time. Remove them from the water using a large flat spatula.
Place pretzels on baking sheet lined with parchment paper or silpat mat.
Using kitchen sheers, cut two ears. Beat one egg yolk. Brush the top of each pretzel bunny with the beaten egg yolk.
Bake until dark golden brown in color, approximately 8 minutes. Add eyes with edible marker after pretzels have cooled.