Preheat oven 350F. Line 2 baking sheets with parchment paper.
In a medium bowl, whisk together the dry ingredients (flours, starch, baking soda, baking powder, salt) and set aside.
Whisk the butter/oil and sugar together.
Add the egg and vanilla extract and whisk until smooth, about 1 minute.
Add the dry ingredients to the wet and use a spatula to mix until just combined.
Fold in the chocolate and cranberries.
If you didn't let your butter/oil cool enough and the dough is too runny, just pop it in the fridge for 30 minutes before scooping.
Scoop tablespoon size servings of dough onto the baking sheets, 2 inches apart (these cookies spread, so leave enough space!).
Bake for 8-12 minutes, until edges are just golden. Sprinkle with flaky sea salt upon removal. Let cookies cool on cookie sheet for 5-10 then transfer to a wire rack.