Korean Pancakes

INGREDIENTS
1 bunch green onions/scallions (1 bunch = 10 stalks)
1 large egg (50 g w/o shell)
1 red bellpepper (evtl)
4 oz shrimp (4 oz = 100 g) (cleaned and deveined)
1-2 Tbsp neutral-flavored oil (vegetable, canola, etc)

Batter
70 g cake flour (70 g = ½ cup + 2 Tbsp) (See Notes)
½ tsp kosher/sea salt (I use Diamond Crystal; Use half for table salt)
½ cup cold water (½ cup = 120 ml)