Roast Beef-Spiced Steak Salad w/ Horseradish Dressing

I did a trial of PLATED, the meal delivery service and this was one of our meals.

2 plum tomatoes, quartered lengthwise
4 cups arugula
2 slices sourdough bread, cut diagonally
1 lemon
2 garlic cloves
10oz inside round steak
Spice mix:
    1/4 tsp onion powder
    1/8 tsp dried oregano
    1/8 tsp dried basil
    1/4 tsp cracked black pepper
    1/4 tsp garlic powder
1 tbl horseradish
1/4 cup mayo

1. Preheat oven to 450, halve the lemon, mince 1 garlic clove, pat steak dry
2. Roast tomatoes - put skin side up, drizzle with oil and season w/ salt and pepper, roast until shriveled and tender, about 8-10 minutes. Remove from baking sheet and set aside
3. Roast steak - while tomatoes roast, put steak round side up on another baking sheet. Season with salt then season with the spice mix. Roast about 10 min, remove and set aside from 5 min
4. dressing - whisk horseradish, mayo, juice of 1/2 lemon and garlic. Add in salt and pepper to taste
5. toast - heat 1 tbl oil in large pan, when it's simmering add bread and toast until golden. Remove and rub the whole garlic clove on one side
6. Slice steak against the grain as thinly as possible. Add arugula to bowl with dressing and toss to coat. Divide and top with tomatoes and steak and serve with steak on the side.