Step 1In a medium bowl, whisk together the sour cream, heavy cream, paprika and salt. Taste and adjust the seasonings as desired. Thin with milk, if desired, 1 tablespoon at a time. The finished creme should have a sauce-like consistency.
Step 1Char the tomato: Heat a grill pan or grill over medium-high heat until hot. Add the tomato and sear, charring until all sides are blackened and blistered. Remove from heat and set aside until cool enough to handle, then crush. Meanwhile, brush the baguette slices with a little olive oil and season with a little salt. Grill the slices until lightly toasted on both sides. Remove from heat and set aside.
Step 2Heat a saute pan or skillet over medium heat until hot, about 2 minutes. Add 2 tablespoons butter, and swirl the pan to melt the butter. Add the Brussels sprouts with one-fourth teaspoon salt, and saute until the sprouts are lightly colored, about 4 minutes, stirring or shaking the pan frequently.
Step 3Add an additional tablespoon of butter and continue to cook until the Brussels sprouts are golden-brown, about 3 minutes, stirring or shaking the pan frequently.
Step 4Add the remaining tablespoon of butter and an additional one-eighth teaspoon of salt and toss to coat. Toss in the scallions and cook for about 30 seconds, shaking the pan, to marry the flavors. Stir in the crushed tomato. The Brussels sprouts should be a rich golden to deep brown on all sides and should not be soupy from the tomato; if the tomato is a bit thin, continue to cook for a minute or two until it thickens. Remove from heat.
Step 5To serve, divide the baguette slices between 2 plates. Spoon over the Brussels sprouts and drizzle over the paprika creme. Serve immediately.