Place the brown sugar in a large mixing bowl and pour the warm water over. Stir to combine, and sprinkle the yeast over the surface. Allow to proof for 5-10 minutes, or until foamy.
Stir in the oil, and add the flour, a cup at a time. When the dough starts to form a ball and pulls away from the sides of the bowl, transfer it to a lightly floured surface and knead for 5 minutes. (You may not need all of the flour.) If the dough seems very sticky, knead in up to 1/3 cup additional flour, as needed.
Lightly mist the mixing bowl with non-stick spray and place the dough inside. Cover with plastic wrap, and allow to rise in a warm place, about one hour, or until doubled in size.
Punch down the dough, divide it into 12 equal balls, and roll each into a rope about 8 inches long. Flatten slightly, and place about 2 tablespoons of peanut butter chips down the center. Bring up the long sides of the dough around the peanut butter chips, carefully pinching to seal them inside. Roll the filled rope again, to a length of about 12-14 inches, and twist into a pretzel shape.
Place the stuffed pretzels on a lightly greased baking sheet, and allow to proof, uncovered, for about 30 minutes.
Preheat the oven to 450 degrees F. Bring about 2 quarts of water to a simmer in a wide, shallow pot. Add the baking soda. The mixture will bubble up for a few seconds. Boil the pretzels, a few at a time, for about a minute on each side. Drain on clean kitchen towels and place on parchment-lined baking sheets.
Brush with egg wash and sprinkle with salt. Bake for 16-20 minutes, or until deep golden brown. Serve warm with Vanilla Malted Cream Cheese Banana Chocolate Dip.