Ottolenghi and Tamimi describe this salad as "summer bliss, offering contrasting textures and aromas," and I could not agree more. I used white doughnut peaches and they were the best choice when I shopped for my ingredients, but yellow peaches would add a deeper lovelier color to this salad. You may also skip the grilling step completely and just add raw peach segments to cut down on the prep time and clean up afterwards.
Cut the peaches in half and remove the pits. Slice each half into 3 wedges, place in a bowl, and add the olive oil and some salt and pepper. Toss well to coat them.
Place a ridged grill pan over high heat and leave for a few minutes so it heats up well. Place the peach wedges on the pan and grill for a minute on each side. You want to get nice charcoal lines on all sides. Remove the peaches from the pan and leave to cool.
To make the dressing place the orange blossom water, vinegar, and maple syrup in a bowl and whisk to combine. Drizzle the oil in slowly while you whisk to get a thick dressing. Season to taste.
On a serving platter, arrange layers of peach, endive, watercress, chard and speck. Spoon over enough dressing to coat all the ingredients but not to drench them. Serve straight away.