Gather your equipment: a large heavy-bottomed pot, a sharp knife, a cutting board, and a wooden spoon.
Peel and chop the carrots into 1-inch chunks, and do the same with the potatoes, aiming for even pieces to ensure uniform cooking.
Heat the oil over medium heat until shimmering, then add the chopped onion. Cook, stirring occasionally, until golden and fragrant, about 5 minutes.
Stir in the cumin and turmeric, cooking briefly for about 30 seconds until aromatic, then add the grated ginger and cook for another minute.
Add the chopped carrots and potatoes to the pot, stirring to coat them with the spices. Cook for 3-4 minutes until they start to soften and release their aroma.
Pour in the coconut milk along with a half cup of water or broth, then bring the mixture to a gentle simmer.
Reduce the heat to low and cover loosely, letting the curry simmer for 20-25 minutes, stirring occasionally, until the vegetables are tender and the sauce has thickened slightly.
Uncover and cook for another 5 minutes to allow the sauce to reduce further, stirring gently. Taste and season with salt as needed.
Remove from heat and let sit for 5 minutes to allow flavors to deepen. Serve hot, garnished with herbs if desired, alongside rice or bread.