2000 calories a day, two people, 7 days, so around 28,000 calories

The absolute lightest you can get that is around 4.5kg(10lbs) of peanut butter.

I'm assuming you have unlimited water at the location.

To make a meal plan that's actually edible for an entire week, I'd suggest you'll need a bit more than that. So maybe bring only 1kg of peanut butter.

Premade pancake mix that only requires water, and the flavored instant oatmeal packets would be good for breakfast. Both go well with some peanut butter in or on top of them for extra calories. Some jam wouldn't hurt either.

You should probably bake some bread so bring some flour, a little bit of salt, and yeast, then bring butter and cheese to spread/put on top. A can or two of tuna is a good here to add protein/flavor/variety, you can make a cheese tuna melt on your fresh bread. You can also make peanut butter and jam sandwiches.

Switch up your carb for dinner to rice, brown would be best if you aren't so worried about cooking time. Try looking up recipes for a Dahl for a couple nights, you'll need to bring lentils, onion, and spices. I'd also suggest making a pulled pork which will feed you for 2-3 days if you bring different sauces (bbq, teriyaki, etc.) For the third dinner, I'd probably try to bring some sausages and do them up in a tomato sauce over the rice with some cheese on top.

Then for fruits and veggies, I'd fill out whatever space/weight I have with some bananas, apples, and carrots because they're easy, cheap, and transport well.

The only refrigeration you need during the trip is for the Cheese, Pork, and Sausages, which should fit into a smaller cooler with an icepack.

You're probably looking at around 30-40lbs of food all in.