Combine vinegar and garlic together in a medium bowl. Set aside.
In a large nonstick skillet, heat 2 tablespoons of olive oil over medium high heat. Add red pepper and cook until lightly browned and beginning to soften, about 2 minutes. Add asparagus and cook until nearly tender, about 2 minutes. Add shallot and cook until softened, about 1 more minute. Remove from heat and add remaining teaspoon of sherry vinegar. Stir in cooled barley. Set aside to cool while you make the vinaigrette.
Whisk remaining 4 tablespoons of olive oil into garlic and sherry vinegar mixture. Season to taste with salt and pepper.
Toss spinach with 2 tablespoons of vinaigrette in a large bowl. Season to taste with salt and pepper.
Add asparagus and barley mixture to the medium bowl with the remaining vinaigrette. Toss to combine. Season to taste with salt and pepper.
To serve, create a bed of spinach on the bottom of each plate. Arrange the asparagus and barley mixture over the top. Sprinkle with toasted almonds and crumbled goat cheese.