At 300 degrees for 12 or more hours you could put sweet potatoes out to cook and they'd be done by dinner, or you could fill up a dutch oven in the back of your truck and slow cook all day. Ok...seriously, tuna and chicken in sealed foil pouches (I bet you can find some without additives), fire up a dehydrator and toss in squash, sweet potatoes, berries, and tropical fruits if you eat them. Make homemade jerky while you're at it...better and cheaper. I make single serve crustless quiches in a muffin tin with lots of veggies and just enough egg to hold together...they freeze well enough and should thaw out or keep cool in a cooler. I think zucchini sticks and prosciutto (without nitrites) at almost any temperature is great. Celery and nut butter. most of this stuff can be eaten with a wax paper wrapping too.

One thing I learned many years ago is that cheap no-name coolers don't keep ice anywhere near as long as better quality brand named coolers, in my case, Coleman. Also, you need to size your ice for the conditions. It could be that to keep your food cold in that heat, you may need to have anywhere from 3-6 less than full (to allow for expansion) liter bottles of water, frozen solid. It might even take a big chest cooler full of frozen bottles to keep one little container of beef and broccoli salad cool, but it can be done.

I've pours a lot of concrete in my time, but never the black stuff! Ouch! Pretty Primal though. Good luck!

When I need to keep stuff in a cooler on really hot days, I use a larger cooler and fill it with bigger hunks of ice. The thicker the hunk of solid ice, the longer it takes to melt.

Gallon-sized ziplock freezer bags, filled most of the way with water and frozen in a home freezer, make good ice blocks. So do gallon- or even half-gallon plastic milk jugs. They can take 2-3 days to freeze solid, however, so keeping enough on hand to keep a cooler chilled every day might be a problem unless you have lots of extra freezer space.

Then, when you put the cooler in your vehicle, insulate it further by burying it under old blankets, towels, etc. That alone can make a huge difference on a hot day.

I would still keep these items in a cooler, but here goes: Canned salmon could work.. I recommend Raincoast wild salmon with a pull tab lid; bring a lemon to squeeze over top. Whole avocados sliced in 2 when you are wanting them andeaten with a spoon.

This is a tricky one- is there any way the company would investing one of those coolers that you can plug in / make arrangements for the employees? What do your coworkers do? Is there a lunch truck where you could get some fresh produce? Sure, it may not be organic, but it's something:)

Imagine you're in Kenyan summer 3 Million BC. Walking all day. Hotter than blazes.

What you're doing behind that paver is 90% of what paleo life was. And the other 10% - Whole30 - bears little resemblance to what you would have been eating in the high carb season of central Africa. I'd recommend scrapping it until paving season is over. Eat fresh fruit and root vegetables like carrots to satiation along with canned or smoked fish. Those should hold up in the heat.

Sounds a lot more fun than sitting in front of this laptop. You're lucky to be able to live paleo.

it's probably a matter of eating a HUGE breakfast of slow digesting foods. and eating some jerky during, or some form of carbs if you can, then a lot of carbs after with your protein and fats.

I work construction as well. From my commute untill I get back home from training 5:30am-9:00pm. I do somewhat of a "Warriors Diet". Here's what I do. Maybe it'll spring some creative ideas for you.

Skip breakfast Sardines, avacado, boiled eggs, fruit, pretty much any canned seafood, eat tupper wear stored food first. (Less exposure to PBAs) Eat bigger meal at home IF