Sheet Pan Balsamic Salmon and Vegetables

Balsamic glaze:

1. To a high-sided medium/large kettle (use one bigger than you think you need), add the 500 ml vinegar, 1/2 cup sugar, and heat over medium to medium-high until mixture boils and can sustain a fast rolling boil.
2. Boil for about 15 to 20 minutes, or until reduced by about 80% and has thickened and is syrupy; stir intermittently and keep an eye on it so it doesn't bubble over.
3. When the sauce looks like it's about halfway done, taste the sauce, and if it's too vinegary and bitter for you, add part of or all of the remaining sugar. I personally use almost 1 cup. Sauce will thicken up more as it cools. Alternatively, you can use store bought balsamic glaze.

Salmon:

1. While making the glaze, preheat oven to 375F (use convection if you have it), line a baking sheet with aluminum foil for easier cleanup (highly recommended), and spray with cooking spray.
2. Place the salmon skin-side down on the baking sheet, and nestle the broccoli and portobellos directly around it, evenly spaced, and evenly drizzle with olive oil; set aside until the balsamic glaze is ready.
3. Evenly drizzle the salmon with about 1/4 cup balsamic glaze using a small spoon, and drizzle the vegetables with an additional 1/4 cup, or to taste.
4. Evenly sprinkle with salt and pepper, to taste.
5. Bake for about 8 to to 12 minutes if using 3 to 4 individual salmon filets, or about 12 to 15 minutes if using 1 large salmon filet, or until the salmon is done to your liking, noting it will continue to carryover-cook a bit after you pull it out of the oven; don't overcook is my recommendation.
6. If desired, after cooking, evenly drizzle with additional glaze, to taste, and serve immediately.