Heat a medium dry pan over medium-high heat. Add bacon*; cook, turning occasionally and adjusting heat if browning too quickly, until crispy, 6-10 minutes.

Turn off heat; transfer to a paper-towel-lined plate. Once cool enough to handle, roughly chop.

Carefully discard all but a thin layer of bacon fat from pan.

While bacon cooks, wash and dry produce.

Trim and halve pear; thinly slice.

In a small bowl, whisk together vinegar, mustard, 2 TBSP olive oil, and ½ tsp sugar (4 TBSP olive oil and 1 tsp sugar for 4 servings) until smooth. Season with salt and pepper.

Heat pan with reserved bacon fat over medium-low heat. (TIP: If pan seems dry, add a drizzle of oil.) Add panko, walnuts, ¼ tsp thyme (½ tsp for 4 servings), and a pinch of salt. Cook, stirring, until golden brown, 1-2 minutes. Turn off heat; transfer to a plate.

In a large bowl, toss mixed greens and pear with as much vinaigrette as you like.

Divide between shallow bowls and top with Parmesan, bacon, and panko topping. Serve.