Steamed brown rice, Asian greens, coriander sprigs, lime wedges, to serve
Preheat oven to 170°C (150°fan-forced).
In a small food processor blend lemongrass, garlic, onion and oil until finely chopped.
Spray a large ovenproof casserole dish with oil and heat over medium-high heat. Brown beef, in batches, and set aside on a plate. Spray dish with a little extra oil, if necessary, reduce heat to medium and add lemongrass paste. Cook, stirring, for 2-3 minutes or until fragrant. Return beef to dish with coconut milk, fish sauce and lime leaves. Add stock, stir to combine and bring to the boil. Cover with lid and cook in oven for 1 ¼ hours.
Add sweet potato to dish and cook, uncovered, for 15-20 minutes or until beef and sweet potato are tender. Remove from oven and stir in beans and spinach. Replace lid for 5 minutes. Skim off any fat that has risen to the top of the dish. Season with pepper and add extra fish sauce to taste, if desired.
Serve beef with rice, Asian greens, extra kaffir leaves, coriander and lime wedges.
Gravy beef or blade steak would also work well in this recipe.
Swap sweet potato for potatoes or butternut pumpkin if desired.