Preheat the oven to 220C, fan-forced. Line 2 oven trays with baking paper. Bring a medium saucepan of salted water to the boil for the spaghetti. Crush or finely chop the garlic. Finely chop the thyme leaves, discarding the tough stems. Coarsely chop the broccoli stem, then cut the head into small florets. Halve the zucchini lengthwise and cut into 1cm chunks.
Step 2 — Roast vegetables
Put the garlic, thyme and broccoli on a lined tray, drizzle with 1 tbs olive oil, season with salt and pepper and toss to coat. Roast for 10 mins or until starting to soften. Add the zucchini to the tray with the broccoli and toss to combine. Roast for a further 8-10 mins until the vegetables are golden and tender.
Step 3 — Make crumbs and stock
Meanwhile, coarsely chop the garlic bread into small chunks and put on the remaining lined tray. Add the almonds and drizzle with 2 tsp olive oil. Season with salt and pepper and toss to coat. Roast, turning halfway, for 8-10 mins until golden. Crumble 1 stock cube* into a heatproof jug, add 125ml (½ cup) boiling water and stir to dissolve.
Step 4 — Cook spaghetti
While the crumbs are roasting, add three-quarters of the spaghetti* to the pan of boiling water (if you're tempted to throw in all the spaghetti, just note the dish won't be as saucy). Cook, stirring occasionally, for 12 mins or until al dente. Drain and return to the pan.
Step 5 — Make cheese sauce
While the spaghetti is cooking, coarsely grate the cheese. Melt 10g butter in a small saucepan over medium heat. Add 2 tsp flour and cook, stirring, for 2 mins or until foaming. Gradually add the stock and 125ml (½ cup) milk, stirring constantly to prevent lumps forming. Bring to a simmer and cook, stirring, for 1-2 mins until thickened. Stir in the cheese.
Step 6 — Get ready to serve
Add the spinach, cheese sauce and half the roasted vegetables to the spaghetti and toss to combine. Taste, then season with salt and pepper. Divide the spaghetti mixture and the remaining roasted vegetables among bowls. Scatter with the garlic bread crumbs and almonds to serve.