In a large bowl, dissolve yeast in warm water. Let stand 5 minutes. Whisk in warm milk, sugar, and salt until combined. Stir in flour until a ball of dough forms.

Turn dough onto a floured surface and knead until smooth and elastic, about 5 minutes. Place dough in a greased bowl, turning once to grease top. Cover bowl with plastic wrap and let rise in a warm place until doubled, 1-1/2 to 2 hours.

Punch risen dough down and divide into 4 pieces. Roll each piece out on a floured surface into a 12x4 rectangle. Sprinkle 1/4 cup cheese over 1/3 of long side. Starting with the cheese-filled side, roll dough up as tightly as possible, pinching edges to seal. Cut filled dough rope into 1 in pieces and place on a parchment-paper lined baking sheet. Repeat step 3 with remaining 3 portions of dough. Allow the pretzel-dough bites to rest 30 minutes.

In a large saucepan, bring 6 cups water to a boil. Dissolve baking soda in boiling water. Working in batches, place pretzel bites in boiling water, seam-side down. Boil pretzels on one side 10 seconds then flip to other side for an additional 10 seconds. Remove pretzels with a slotted spoon to a parchment paper-lined baking sheet. (place them seam-side down)

Bake pretzel bites at 400F 10-15 minutes or until golden brown. Sprinkle with sea salt if desired.