Place the sweet potatoes in a large pot or dutch oven and cover them completely with water. Bring water to a boil. Reduce heat and simmer for 20 minutes or until the potatoes are tender. Drain the water and allow the sweet potatoes to cool for 15 minutes.

Preheat oven to 350°F (177°C). Grease a 9×13-inch baking pan (or a similar size casserole dish, or a 12-inch oven-safe skillet). Set aside.

Place the cooked sweet potatoes in a large mixing bowl. Using a handheld or stand mixer, beat the potatoes until relatively smooth—I like to leave some chunks for texture. For your reference, you will have about 4 cups of mashed sweet potatoes. Add the butter, brown sugar, beaten eggs, half-and-half, vanilla, and salt. Spoon/pour the mixture into prepared pan.

In a medium bowl, whisk the flour, brown sugar, and cinnamon together. Using a silicone spatula, fold in the melted butter and pecans until the mixture is totally combined. Spoon evenly over potatoes.

Bake for 30–40 minutes or until golden brown on top. Allow to cool for 5 minutes, then top with a little fresh thyme or rosemary and a sprinkle of sea salt. Serve warm.