Peel and chop the yellow potato into 1-inch cubes and place them in a pot of cold salted water.
Bring the potatoes to a boil and cook for 12-15 minutes until fork-tender.
While potatoes boil, season the steak generously with salt and black pepper on both sides.
Heat the olive oil in a heavy skillet over medium-high heat until shimmering.
Place the steak in the skillet and sear for 4-5 minutes per side for medium-rare, or until it reaches your desired doneness.
Remove the steak from the pan and let it rest on a cutting board for at least 5 minutes.
Steam the broccoli florets in a steamer basket over boiling water for 4-5 minutes until bright green and tender-crisp.
Drain the potatoes and return them to the pot with the minced garlic, grass-fed butter, and a splash of water or unsweetened almond milk.
Mash the potatoes until smooth and creamy, seasoning with a pinch of salt if needed.
Slice the rested steak against the grain and serve immediately with the garlic mash and steamed broccoli.