Hull and then cut the strawberries into thin slices. If your almonds aren't already toasted, toast them at 350°F for 10 to 12 minutes, until darkened and very fragrant. Set aside a few of the strawberry slices, a few almonds, and some of the goat cheese to sprinkle over the top of the salad.
Transfer the spinach to a large mixing bowl. Drizzle a tablespoon of the poppy seed dressing over the greens and toss gently to coat. Continue adding tablespoons of dressing as needed until the greens are all evenly slicked with dressing. Gently toss the sliced strawberries, almonds, and goat cheese with the spinach.
Transfer the salad to a large serving bowl. Sprinkle the reserved strawberries, almonds, and goat cheese over the top, along with one last drizzle of dressing.
DRESSING: Whisk the white wine vinegar and sugar until the sugar is mostly dissolved (it's okay if there is still some undissolved sugar); Peel the shallot and grate it on the smallest holes on a box grater directly into the bowl; Add the poppy seeds, salt, and ground mustard, and whisk to combine; Whisking the dressing steadily, pour the olive oil into the dressing in a slow stream. Continue whisking until completely combined; Transfer to a covered container and store in the fridge for several weeks. The dressing will separate as it sits; shake to recombine before using.