1. Set the oven rack in the middle of the oven and preheat to 325^oF (165^oC).
2. Lightly spray a 10 x 15-inch baking pan with vegetable or canola oil spray and set it aside.
3. In a large bowl, add 4 cups regular rolled oats, 3 cups unsweetened shredded coconut, 1 cup all-purpose flour, 1 1/2 cups granulated sugar, 1/2 tsp table salt, and 1 tsp ground cinnamon. Mix well so everything’s evenly combined.
4. In a microwave-safe bowl, melt 1 cup of butter together with 3 Tbsp golden syrup or honey.
5. Let this mixture cool for about 5 minutes so it doesn’t activate the baking soda too fast later.
6. In a small cup or bowl, stir 2 tsp baking soda into 1/4 cup low-fat milk, mixing until fully dissolved.
7. Pour the slightly cooled butter mixture and the milk mixture into the dry ingredients.
8. Mix really well using a sturdy spoon or your hands. It should feel sticky and evenly coated, not dry or crumbly.
9. Press the mixture firmly and evenly into the prepared pan, making sure the corners are well packed down. 
10. Bake for 25 to 35 minutes, rotating the pan after 16 to 18 minutes for even browning.
11. If the top starts browning too quickly, loosely cover with foil and, if needed, reduce the oven temperature to 300^oF (150^oC) for the last 5 to 10 minutes.
12. Remove from the oven and place the pan on a wire rack.
13. Let the crunchies cool for 10 to 12 minutes, then cut into squares while still warm.
14. Waiting too long makes them harder to cut cleanly.

Notes

1. For chewier crunchies, bake closer to 25 minutes.
2. For crisp, snappy squares, go closer to 35 minutes.
3. Cut foil to fit the pan before baking so it’s ready when you need it. Rotate and cover quickly to keep oven heat steady.
4. If the bottoms brown too fast, place the pan on top of a second baking tray for insulation.
5. Don’t use quick-cooking oats; regular rolled oats give the best texture.
6. Lyle’s golden syrup gives the most classic flavor, but honey works in a pinch.
7. Store in an airtight container for up to 1 week.