Preheat the oven to 400°F and line a baking sheet with foil.
Brush the sweet potatoes with a small amount of olive oil, place them on the baking sheet, and bake until tender, 45 minutes to 1 hour.
To make the honeyed tahini, in a small bowl, whisk together the tahini, honey, half the lemon juice, the grapeseed oil, and a generous pinch of sea salt. If needed, loosen with a small amount of water. Set aside.
To make the herb and nut topping, in a medium bowl, toss the parsley, tarragon, mint, and chives. Melt the butter in a medium skillet over medium heat; add the almonds and fry, stirring often, until they are golden brown in color and smell nutty, about 3 minutes. Pour the butter and nuts over the herb mixture and toss to combine. Season with sea salt and the remaining lemon juice.
Split each baked sweet potato down the center, drizzle generously with the honeyed tahini, and top with the fried almonds and herbs.