Spread baking soda on a foil-lined sheet pan and bake for 45 minutes - 1 hour. Let it cool and combine with bread flour in a bowl.
Add the warm water, stirring and mixing to form a crumbly dough.
Knead it together for 5 minutes. Wrap the dough in a plastic and let is rest in room temperature for 10 minutes, then knead for another 5 minutes. Wrap the dough and put it in the fridge for 1 hour.
Divide the dough into 4 portions. Flatten the dough using a rolling pin; then roll each dough using a pasta machine.
(Note: I start with #7 few times; then change to #5; then to #3). You can set the thickness of your noodles/ ramen. Keep the noodles well floured to prevent them from sticking and bundle into each portion.
Add water to a pot and bring to a boil. Add the fresh pasta and cook for 2-3 minutes, or until al dente.
For the Spicy Oil:
Add the vegetable oil to a cooking pot. Let it cook on a medium-low heat for 2-3 minutes. Add the leek, garlic, and ginger; then cook for 20-30 minutes. Remove leek, garlic, and ginger.
Add the chili powder and cook for 10 minutes. Let it cool and strain the chili powder out.
Add 2-3 tbs of spicy oil to one portion. Mix well and add your toppings on top.