Divide spices and place them in two tea bags.
Remove any imperfect outer leaves and finely shred cabbage heads around their cores. Cabbage cores won't be used. Shred carrots.
Place a large bowl on kitchen scales, zero it, and add 11 oz of shredded cabbage, 0.2 oz of salt, 1 tsp agave syrup, a third of carrots. Mix and toss for about 30 seconds. Transfer into a jar. Place one tea bag with spices on top.
Repeat with the second third of the cabbage. Press down the cabbage in the jar with your fist. Place the second tea bag with spices on top.
Repeat with the last third of the cabbage. Press down the cabbage in the jar with your fist. Place the weight on top. Ferment for three days in room temperature (72F). At the end of the second day of fermentation, help by-product gases escape from the bottom layers of cabbage by making 4-5 deep holes with a chopstick.
Keep refrigerated in covered containers for up to 1 month. (The fermentation process slows down in lower temperatures, but it continues.) To serve as a salad, mix sour cabbage with thinly sliced onions and dress with high quality vegetable oil.