Pretzel dough: Combine water, brown sugar and yeast in the bowl of a stand mixer and mix with the dough hook until combined. Let sit for 5 minutes.
Add melted butter, beer, salt, and flour to the mixture. Mix on low speed until combined. Increase to medium speed and continue kneading until the dough is smooth and begins to pull away from the sides of the bowl, about 3 – 4 mins. Remove dough from bowl and knead into a ball with your hands.
Coat a large bowl with oil, add dough and turn to coat with the oil. Cover with a clean towel and place in a warm spot until the dough doubles in size.
In the meantime, make the filling: Fry bacon until crispy. Remove with a slotted spoon and drain on paper towels. In the same skillet, melt butter, add garlic, and cook for a couple of minutes. Whisk in flour until it makes a paste. Cook over medium-low heat for 1-2 mins, then pour in milk. Stir and cook 1 more minute.
Add cream cheese, mozzarella, Parmesan and black pepper. Stir until cheeses are melted. Stir in yogurt until smooth. Add chopped artichokes, spinach, and bacon, and stir to combine.
Preheat the oven to 425 degrees F. Bring a large pot of water to a boil.
When pretzel dough has doubled, punch down and divide into 8 equal balls. Roll each out into a 11×3 inch rectangle. Spread about 2 Tbsp dip filling along the length of each piece. Roll the dough up into a log, enclosing the filling inside. Pinch the seams together and then very gently roll the dough with your hands to form an even cylinder and fully enclose the filling. Form into a pretzel shape, and press to seal.
Slowly add the baking soda to the boiling water. Boil the pretzels in the water solution, 2 at a time for 1 minute, splashing the tops with the warmed water using a spoon. Remove with a large flat slotted spatula.
Place pretzels on baking sheet about 2 inches apart. Brush tops with beaten egg and season liberally with sea salt.
Bake for 15 to 18 minutes or until pretzels are golden brown.
Remove pretzels from oven and let cool five minutes.
If made ahead, you can reheat the pretzels at 350 degrees F. for 15 minutes or until warm. (But they are BEST fresh out of the oven!)