Heat oil over medium-high heat in a large skillet. Add scallion whites; sauté until softened, 3 to 4 minutes. Add seasonings; cook until fragrant, a minute or so. Add white beans and tomatoes and bring to a simmer. Reduce heat to medium-low; simmer, stirring occasionally, until liquid thickens to stew consistency (beans will just start to stick to pan bottom), 10 to 12 minutes. Stir in dill and serve.