Baking Soda Sunday Roastie
Prátaí Rósta·(praw-tee rohs-tuh)
Purdies – The Sacred Spud
If there is one thing an Irish grandmother treats with deadly, uncompromising reverence, it’s the Sunday roast potato. In the motherland, they rely on a pinch of pantry bread soda in the boiling water to violently break down the potato's exterior, creating a starchy slurry that eventually fries into a thick, glass-like crust. To replicate that magnificent, shattering crunch in an American kitchen, you trade the Irish Rooster for a high-starch Russet and hit it with a mix of olive oil and leftover Sunday bacon grease in a screaming hot oven. No frills, no culinary school pretense—just the loud, deeply savory taste of home.
Before you start
Preheat the oven to 425°F.
Ingredients
- Russet potatoes3 lb
- baking soda1/2 tsp
- Kosher salt1 tbsp
- olive oil3 tbsp
- bacon grease2 tbsp
- garlic5 med cloves
- fresh rosemary3 sprigs
- black pepper1 tsp
- flaky sea salt1 tsp
Method
- 01
Boil the potatoes in alkaline water.
Place the potatoes in a large pot, cover with cold water, and add the kosher salt and baking soda. Bring to a rolling boil over high heat, then drop to a simmer for 8 to 10 minutes until a fork slides in with a little resistance but the potatoes are not falling apart.
- 02
Preheat the fat in the oven.
While the potatoes finish boiling, put the olive oil and bacon grease into a large roasting pan or rimmed baking sheet and slide it into the hot oven.
- 03
Drain and rough up the potatoes.
Drain the potatoes in a colander and let them steam dry for exactly one minute. Vigorously shake the colander to literally rough up the edges of the potatoes until they are coated in a thick, starchy sludge.
- 04
Tumble the potatoes into the screaming hot fat.
Carefully pull the hot roasting pan from the oven and add the potatoes so they sizzle instantly upon contact. Toss them gently to coat every side, then spread them out evenly so they roast rather than steam.
- 05
Roast the potatoes undisturbed for twenty minutes.
After twenty minutes, remove the pan, gently flip each potato to expose a new flat side to the hot metal, and return to the oven for another twenty minutes.
- 06
Add the aromatics for the final stretch.
Toss in the smashed, unpeeled garlic cloves and rosemary sprigs, give the pan a gentle shake, and roast for a final 10 to 15 minutes until deeply golden and crusty.
- 07
Season generously and serve immediately.
Transfer the potatoes to a bowl, leaving the excess fat behind, and toss with flaky sea salt and coarsely ground black pepper.
Notes
Use a high-starch potato.
The American Russet is the closest equivalent to the floury Irish Maris Piper or Rooster, interacting perfectly with the baking soda to create the essential crispy crust.
Do not peel the garlic.
Leaving the skins on prevents the garlic from burning into bitter ash during the long, high-heat roast, allowing it to caramelize into a sweet paste inside.
Make ahead for busy weeknights.
You can boil, chuff, and toss the potatoes in fat the night before, keeping them covered in the fridge overnight before sliding them straight into the hot oven the next day.
From Cook Irish-American Food.