To make the dressing, in a large bowl whisk together the olive oil, lemon juice, garlic, Dijon mustard, thyme, and salt and pepper to taste (I like 1/2 teaspoon salt and 1/8 teaspoon pepper).: The bowl will smell bright and savory as you whisk, the citrus should cut through the raw garlic aroma and the Dijon mustard will help the mixture thicken slightly into an emulsion. Whisk until you feel the dressing thicken, that gentle resistance means the olive oil and lemon are combined. If the dressing separates, keep whisking or add a tiny splash more lemon and mustard to stabilize it. A frequent misstep is overpacing the oil while whisking, which can prevent proper emulsification, so add the oil slowly and keep whisking steadily.
To the bowl with the dressing, add the salad greens and toss to combine. Top with beets, goat cheese, and almonds and serve. Dressed salad greens may also be divided among individual plates before adding beets, goat cheese, and almonds.: When you add the mixed field greens to the vinaigrette, you should hear a soft rustle as leaves move and see them become lightly glossy with dressing. Toss gently but thoroughly so each leaf gets a thin coating rather than puddles forming at the bottom. The reason we dress the greens before adding harder toppings is to ensure every leaf carries flavor, and that prevents the beets from making everything too wet. A common error is overdressing, which makes the greens limp, so start with less and add more if needed.
Top with beets, goat cheese, and almonds and serve: Arrange the tender roasted beet pieces across the dressed greens for color contrast, then scatter crumbled goat cheese so some melts slightly onto warm beet if they are warm, offering creamy pockets in every bite. Finish with the toasted slivered almond s for crunch. The visual cue of glossy greens, vibrant beet pieces, and white cheese crumb is what you want to see before serving. Watch for overly large beet pieces which can overwhelm a forkful; aim for bite sized pieces for balance.
Dressed salad greens may also be divided among individual plates before adding beets, goat cheese, and almonds: Plating individually helps with presentation and ensures each person gets a balanced portion of each component. When plating, place the greens gently in a shallow bowl, then layer the beet pieces artistically, finishing with cheese and nuts. The tactile satisfaction of layering contrasts is worth the extra couple of minutes. A typical mistake is piling everything in the center which can hide the greens, so spread components across the plate to show color and texture.