To make the balsamic reduction pour the vinegar into a small saucepan and heat over a medium high heat. Allow to simmer until reduced by half or two thirds at the most (about 15 minutes). Set aside to cool.
Wash spinach and remove any tough stalks. Coarsely chop and place on two salad plates.
Cut avocado in half, peel and coarsely chop. Sprinkle half an avocado over the spinach on each plate.
Slice the strawberries and divide evenly between the plates.
Drizzle with the balsamic reduction and flax oil blend and grind plenty of black pepper over the top. Serve immediately.