1. Preheat the oven to 325°F. Generously butter a 9-by-9-inch glass or metal baking dish.
2. Melt the butter in a heavy-bottomed pot that will hold 2 cups of oats with ample room for stirring. Adjust the flame to medium and stir the oats every minute or so for about 6 minutes. The oats need to be about two shades darker than they are raw; keep a few raw oats on the counter next to you as a reference point.
3. Pour the toasted oats into a large bowl. Wipe out the pot and set it aside to use again for the syrup. Add ½ cup of flaxseed meal and the cinnamon to the bowl.
4. Toss the raisins with the remaining tablespoon of flaxseed meal and chop finely. (Tossing the two together keeps the raisins from sticking to your knife.) Add them to the oat mixture.
5. To make the syrup, measure the honey, brown sugar, molasses, and salt into the reserved pot. Place it over a medium flame, stir to combine, and cook the syrup until evenly boiling, about 6 minutes. Resist the temptation to remove it early--boiling the syrup gives these granola bars real chew.
6. Pour the syrup over the oat mixture, making sure to use a spatula to scrape every last bit out. Then use the spatula to coat every flake with syrup. This means going over and over, tossing and scraping the oats together. Scrape the granola mixture into the prepared pan.
7. To form the bars, butter your hands and press the oats firmly and evenly into the pan.
8. Bake for 25 to 30 minutes, rotating the pan halfway through. The outer edge of the granola bars should be darker than the rest and the bars should have a beautiful sheen. Remove from the oven and let cool for 10 minutes. Cut the contents of the pan into quarters, for a total of 16 bars. Remove the bars from the pan and let cool before eating.
9. The granola bars can be eaten the day they're made, or kept in an airtight container for up to 3 days.