First we’re going to make a roux, but it has a little less fat than a traditional roux, which means it doesn’t get as goopy. If you’d like a more traditional roux, just add extra oil.
Preheat a large, heavy bottom pot over medium-low heat.
Add the oil and sprinkle in the flour. Use a wooden spatula to toss the flour in the oil, and stir pretty consistently for 3 to 4 minutes, until the flour is clumpy and toasty.
Add the onion and salt, and toss to coat the onions completely in the flour mixture. As the onions release moisture, they will coat more and more. Cook this way for 5 minutes, stirring often. Add garlic and stir for 30 more seconds or so.
Stream in the vegetable broth, whisking constantly to prevent clumping. Add the celery, potatoes, carrot, dill, thyme, paprika and black pepper, then turn the heat up and cover to bring to a boil. Keep a close eye and stir often, so that it doesn’t clump or boil over.
Once boiling, reduce the heat to a simmer and let cook uncovered for 20 to 25 minutes, stirring occasionally, until the stew is nicely thickened and the potatoes and carrots are tender.
In the meantime, prepare the dumplings.
Sift the flour, baking powder and salt together in a large mixing bowl. Mix in the rosemary. Make a well in the center and add the milk and olive oil. Use a wooden spoon to mix together until a wet dough forms.
When the stew is ready, mix in the beans and plop dough right on top of the stew in spoonfuls. You should get about 14 dumplings. Cover the pot tightly and cook for about 14 more minutes. The dumplings should be nice and firm. Use your ladle to dunk them into the stew to coat.
Ladle stew into bowls, topped with dumplings. And serve!