Traditionally, Icelandic rúgbrauð is baked in the hot geothermal ground: a low-and-slow process.
The San Fernando Valley isn't geothermal, but we ARE in an extreme heatwave right now.
Let's see if my car can achieve the low-and-slow conditions needed for baking rúgbrauð.
(thread) https://t.co/bX2BrkgUAe

I'm using this recipe: https://www.icelandfoodcentre.com/rugbraud-rye-bread/
I've made this before, in a normal oven.
I used corn syrup instead of golden syrup, and kefir instead of súrmjólk, since I don't know where to find those in the US.
Even with substitutions, this comes close to what I had in Iceland.

When I've made this recipe in the past, I've done the suggested 30 minutes at high heat before turning it lower for 7.5 hours. I'm going to do the whole thing at low heat and for longer, since I think using the oven even a little negates the "can I bake this in my car" question.

Today's "oven" is a 2016 Honda HR-V. It is dark gray, and the interior is black. It gets very hot in there, in general.
I moved it from my usual covered parking place onto an unshaded, east-west-oriented street, to maximize the sunlight it gets today. https://t.co/fYH4V9fWnB

I'd normally use a loaf pan for bread, but I'm using a cast iron dutch oven today, since I figure that will get and stay hotter. After I took this picture, I wrapped it all in plastic wrap, since containing the steam is a big part of the cooking process for this bread. https://t.co/aIIbSINEW8

I parked my car at 11 AM. It was 98°F/36.7°C at the time. Only 30 minutes later, it was already 104°F/40°C outside, and 130°F/54.4°C on the dashboard of my car. https://t.co/ABZjhBZDMZ

My weather apps all say the max temperature today will be 107°F/41.7°C, but they also say it won't get there until 3 PM. At 11 AM, I was measuring temperatures listed for 1 PM. I'm guessing we'll exceed that. That was the deal yesterday, too.

It's currently 12:30 PM PDT; the bread has been in the car for an hour. I figure I'll check it every two hours or so, and I'll update this thread then!

1:30 PM PDT.
The dough has risen and bubbled, to the point where it has overflowed into the plastic wrap.
The dashboard itself clocked in at 187.7°F/86.5°C.
Air inside the car was in the 165°F/73.9°C range.
Outside temps fluctuated as traffic passed, between 111-115°F/44-46°C. https://t.co/ObrDDUBJ5J

3:30 PM PDT.
The temperatures of the dashboard, of the air inside the car, and the air outside the car are basically the same as two hours ago.
More dough has overflowed the pot and into the plastic wrap, but the stuff left in the pot looks like it's changing texture. https://t.co/kb60vVl0Aq

I realize that the street I'm doing this on DOES share a name with a volcano.

5:30 PM PDT.
The car smells nice now!
It has cooled down everywhere; dashboard is 160°F/71°C, air in the car is 140°F/60°C, and it's 105°F/40.5°C outside.
Looks like things are consolidating more, and the stuff that escaped the plastic wrap is starting to feel spongey! https://t.co/NQYLsDVpbt

While a lot of oven recipes say to go anywhere from 8 to 12 hours, apparently it's a full 24 if you cook it with a hot spring. I may need to leave it in the car that long.
(And I may also move the car to a parallel street with the same light conditions but less traffic...)