Mix the cardamom, cinnamon, fennel seeds, cumin and brown sugar together in a small bowl.
Sauté the walnuts in extra virgin olive oil until they turn a slightly darker colour. While they're still hot, toss in the mix of spices previously prepared.
Let cool to room temperature.
Chop the green Gordal olives into medium-sized pieces (think the size of a pine nut).
Place in a mixing bowl and add the vinegar and mustard.
Slowly add the extra virgin olive oil while whisking quickly.
Season with salt and pepper to taste.
Toss the arugula with the vinaigrette, and add salt and black pepper.
Scatter the walnuts along with the additional chopped green Gordal olives and piquillo peppers around the plate.
Garnish the plate with more dressing as well as edible spicy flowers.