Pre-heat oven to 425 deg F
In a large bowl, add the flour, a strong pinch of sea salt, and a grind or two of freshly ground black pepper. Whisk to combine
In a separate bowl, add the eggs and milk. Whisk to combine
Add the eggs to the flour mixture and whisk until just combined.
Stir in the thyme and chives
Over medium-high heat, add the butter to a 12-inch cast-iron (or another oven safe) skillet, and allow it to melt.
Continue to cook, whisking occasionally, until the butter has browned and smells nutty (~ 5-7 min); then swirl it around in the skillet until the sides and bottom of the pan are coated
Pour the batter into the skillet, and scatter the Parmesan cheese and flaky sea salt over the top
Bake until the Dutch baby has puffed and is golden (~ 20-25 min)
** Note: Baking it a little less gives a softer interior though less rise; baking it little more gives you more puff and a drier interior; both ways are wonderful
Serve immediately, garnished with thyme, chives, and (optionally) Sriracha and/or lemon wedges on the side