For the hamburger buns:

Bring the milk to a lukewarm temperature (98°F); pour into a mixer and add the yeast. At low speed, mix for about 10 seconds to dissolve the yeast. Add eggs, flour, sugar and salt; mix for 30 seconds at medium speed. Using the paddle attachment, knead the dough for 5 minutes.

Let the dough rest a few minutes, add the butter and then knead again for another 5 minutes.

Let the dough rest in the bowl, covered, for one hour or until doubled in volume. Then knead again for another 10 minutes.

Remove the dough with well-oiled hands so the dough doesn’t stick to them. Make 4 balls and place them on a baking paper-lined tray. Leave it another hour, in a warm place free of drafts.

Preheat oven to 400º F.

Brush the top of the loaves with a beaten egg and sprinkle with sesame seeds and chopped pistachio. Place the bread into the oven, reduce the temperature to 350° F and bake 20 to 30 minutes. The last 10 minutes cover with aluminum foil so top of bread does not burn.

For the burgers:

Mix the two types of meat and add salt, pepper and chopped pistachios. Form 4 patties and let sit at room temperature. Heat a little oil in a fry pan. Fry each burger over medium heat for 6 minutes on each side. Slice the gherkins and place them on top of the burgers. Place each one into a sliced bun.