Preheat oven to 400 degrees and line a baking sheet with foil or use a nonstick baking sheet. Thoroughly rinse produce and pat dry. Stem cauliflower and trim stem ends, leaving core intact. Place core side down. With a large knife, slice into four ½" steaks from center of cauliflower, reserving any florets that come loose. Mince garlic. Cut tomatoes into a dice. Finely chop parsley. Halve lemon. Cut bell pepper into dice. Drain olives. Dice baguette into ½" cubes.

In a large pen, dry-toast (no oil necessary) the almonds over medium heat, moving the pan back and forth a bit to prevent the almonds from burning. Almonds are done when they are lightly browned and emit a roasted aroma. Remove almonds from pan and set aside.

In a separate pan, sauté 1 Tbsp. olive oil, tomatoes, bell pepper, any loose cauliflower florets (if there are none, that's ok), red pepper flakes, and 1/3 of the garlic until aromatic, about 5-7 minutes. Add half the diced bread (add more for a thicker sauce, if desired) and stir to let soften. Once softened, transfer mixture to food processor or blender. Add juice of 1 lemon to taste, half the toasted almonds, ⅔ of the parsley (reserving the rest for garnish), ¼ cup olive oil (or water or white wine, for a lower-fat sauce), and black olives (reserving a few for garnish). Blend until smooth. Add salt and pepper to taste, return to skillet, and keep warm over low heat until ready to serve.

Working in two batches, cook cauliflower steaks until golden brown, about 2 minutes. Using a spatula, very carefully turn the cauliflower steaks, adding 1 Tbsp. olive oil to pan between batches. Transfer steaks to prepared baking sheet. Sprinkle cauliflower with remaining garlic. Roast cauliflower until tender and browned, about 15 minutes. Remove from oven and allow to cool for 2 minutes before plating.

While the cauliflower is roasting, bring a medium pot with 1 cup of lightly salted water to a boil. Once boiling, remove pot from heat and pour in couscous. Stir to evenly moisten the couscous. Cover the pan and let sit for 10 minutes. If the couscous hasn't absorbed the water or still tastes crunchy after this time, cover and let sit for a few more minutes. Stir in remaining almonds, 1 Tbsp. olive oil, and salt and pepper to taste. Fluff with fork before serving.

Place a serving of couscous on a plate. Nestle a cauliflower steak atop couscous. Smother in romesco sauce. Garnish with remaining fresh parsley and black olives and a crack of freshly ground black pepper.