Mix all of the Cajun seasoning ingredients in a bowl. This makes one batch for this recipe.
Season the Steak
Pat steak cubes dry with a paper towel. In a bowl, toss with Cajun seasoning. Set aside while you prepare the mash.
Make the Sweet Potato Mash
Boil sweet potato in salted water for 15–18 minutes or until tender. Drain well and mash with butter, milk, salt, and pepper until smooth. Add a touch of maple syrup or honey for a subtle sweetness. Keep warm.
Cook the Greens
Blanch broccolini in boiling water for 2 minutes, then drain. Heat olive oil in a pan, sauté the garlic until fragrant, then toss in the greens. Finish with lemon juice and a pinch of salt.
Sear the Steak Bites
Heat a large pan over high heat until just smoking. Add steak in batches and sear for 2–3 minutes until golden and slightly charred. Add butter at the end to glaze and toss. Remove from the pan and rest for 5 minutes.
Optional Pan Sauce
Deglaze the pan with beef stock, Dijon, and Worcestershire. Simmer for 1–2 minutes, whisk in butter until glossy. Spoon over steak when serving or portioning.
Portion
Add a scoop of mash to each container. Top with steak bites and garlic greens. Drizzle with the sauce, if using, and garnish with parsley.
Chef's Tips
Pat the steak fully dry before tossing it with the oil and seasoning — any surface moisture left on the cubes will make the pan steam instead of sear, and you'll lose the char.Sear in batches without crowding the pan, and keep the heat high until it's just smoking — too much steak at once drops the pan's temperature and stops it from developing that charred edge.Add the butter right at the end to glaze the steak, not earlier — butter burns quickly over high heat, so holding it back until the sear's done is what gets you the glaze without bitterness.
Storage & Reheating
Refrigerate for up to 4 days, or freeze for up to 3 months, in an airtight container.To reheat, microwave covered for 2–3 minutes, or warm gently in a pan with a small splash of stock to loosen the mash and sauce. Thaw frozen portions in the fridge overnight before reheating.