Prep the veggies while you heat a Dutch oven over medium heat. Dice the onion. Trim away the dark green tops and root end of the leek and discard/compost/save for stock. Cut the leek in half lengthwise, then cut each of those halves in half again. Thinly slice then place in a colander and rinse well. Set aside to drain. Finely chop the jalapeño. If you want it mild, remove the veins/seeds before chopping. Mince the garlic and chop the thyme leaves. Peel the potato and dice it. Remove the greens from turnips and chop them into pieces of similar size to the potatoes. 

Add oil to the Dutch oven. Once shimmering, add the onion and leek. Season with a pinch of salt. Cook, stirring every minute or so, until the veggies have softened and the onion is translucent (about 3-5 minutes). Add the jalapeño and cook until softened and the onions/leeks are starting to get a bit of color (about 3-4 minutes). Stir in the garlic, thyme, and dried oregano. Cook, stirring constantly, for 2 minutes. Stir in the potatoes and turnips then add the broth (or alternately, the water and bouillon cube). Season with a hefty pinch of salt. Allow the broth to come to a simmer. Simmer for 12-15 minutes or until the potatoes and turnips are fork-tender.

Turn off the heat, then stir in 1 cup of cream. Serve warm garnished with shredded cheddar and sliced scallions if you like. 

Store leftovers in an airtight container in the fridge and enjoy within 5 days.