This turned out delicious, and it is always such a pleasure to cook from the garden - especially when we can add in some of our own home-grown herbs for a superb flavor.
Just to note: I came across another recipe for green beans with golden roasted beets (see: https://www.floatingkitchen.net/green-beans-and-golden-beets-with-tarragon-and-almonds/) which I adapted to combine with the mustard-tarragon dressing. It was really good!
In a mixing bowl, whisk together the vinegar, mustard, shallots, and salt and pepper. Slowly add the oil in a stream and whisk to mix well. Add the tarragon and gently stir. Adjust seasonings and tarragon, to taste.
Heat a flat nonstick pan over medium heat. Toast the almond slices in the pan, stirring occasionally, until slightly toasted. They should take 3 to 4 minutes. Spread the toasted nuts out on a dry towel to cool. Chop the nuts into smaller pieces, once cooled, if desired.
Cut the green beans into approximately 2 inch pieces. Place in a vegetable steamer over boiling water and steam them until al dente (about 5 minutes, more or less). Time will vary based on the freshness of the beans and your preferences as to firmness. Alternatively, you can boil them gently until al dente (which should take less time).
Drain the beans in a colander and immediately place in a serving bowl. Toss with the dressing while still warm. Top with the toasted almond pieces and serve.