Before starting, preheat the oven to 450˚F. Wash and dry all produce. Peel, then cut potatoes into 1-inch pieces. Add potatoes, 2 tsp salt and enough water to cover (by approx. 1 inch) to a large pot (use same for 4 ppl). Cover and bring to a boil over high heat. Meanwhile, strip a few thyme leaves from stems, then finely chop 1/2 tbsp (dbl for 4 ppl).Once potatoes are boiling, reduce heat to medium-high. Simmer uncovered until fork-tender, 10-12 min. Drain and return potatoes to the same pot, off heat. Mash 2 tbsp butter and 1/4 cup milk (dbl both for 4 ppl) into potatoes until creamy. Season with salt and pepper, to taste.

Meanwhile, heat a large non-stick pan over medium-high heat. While the pan heats, thinly slice mushrooms. When the pan is hot, add 1 1/2 tbsp butter (dbl for 4 ppl), then swirl the pan until melted. Add mushrooms. Cook, stirring occasionally, until golden-brown, 3-4 min. Season with salt and pepper. Transfer mushrooms to a plate.

Return the same pan to medium-high. When hot, add 1/2 tbsp butter (dbl for 4 ppl), then swirl the pan until melted. Add bison and mirepoix. Cook, breaking up bison into smaller pieces, until no pink remains, 4-5 min.** Season with salt and pepper. Add 1 tsp thyme (dbl for 4 ppl) and tomato sauce base. Sprinkle Gravy Spice Blend into the pan. Cook, stirring often, until bison and mirepoix are coated, 30 sec. Add mushrooms, broth concentrate, 1 cup water, 1/2 tsp vinegar and 1/4 tsp sugar (dbl all for 4 ppl) to the pan with beef and mirepoix. Cook, stirring often, until filling is combined and comes to a simmer.

Once simmering, cook, stirring occasionally, until mixture thickens slightly, 1-2 min. Season with salt and pepper, to taste. Transfer filling to an 8x8-inch baking dish (9x13-inch for 4 ppl). Dollop mashed potatoes over filling, then spread into an even layer. Sprinkle cheese evenly over top, then sprinkle with as much remaining thyme as desired. Bake cottage pie in the middle of the oven until filling is bubbling around the sides, 12-14 min. (TIP: For a golden top, turn the oven to broil and move the pie to the top of the oven to broil for 1-2 min. Keep an eye on the pie so it doesn't burn!)

Meanwhile, cut tomato into 1/2-inch pieces. Add remaining vinegar, 1 1/2 tbsp oil and 1/4 tsp sugar (dbl both for 4 ppl) to a large bowl. Season with salt and pepper, to taste, then whisk to combine. When cottage pie is done, add spinach and tomatoes to the bowl with vinaigrette, then toss to combine.

Allow pie to cool for 2-3 min before serving. Divide cottage pie between plates. Serve salad alongside.