Adjust racks to top and middle positions and preheat oven to 450 degrees. Wash and dry produce.

Roughly chop spinach. Zest and quarter lemon. Thinly slice each baguette into 8-10 pieces. Dice tomatoes into ¼-inch pieces. Mince chives.

Heat a large drizzle of olive oil in a large, preferably nonstick, pan over medium heat. Add spinach to hot pan. Season with salt and pepper. Cook, stirring, until wilted, 2-3 minutes (for 8 servings, you may need to work in batches).

Add garlic powder and Italian Seasoning; cook, stirring, until fragrant, 30-60 seconds.

Reduce heat to medium low. Stir in Vidalia onion paste, cheese roux concentrate, and ½ cup water (¾ cup for 8). Cook, stirring, until slightly thickened, 1-2 minutes.

Add cream cheese to pan and stir until melted. Remove from heat.

Stir in ricotta and juice from two lemon wedges (four wedges for 8 servings). Taste and season with salt and pepper. Let sit until cooled slightly, about 5 minutes.

While filling cools, halve lasagna noodles widthwise (you’ll make 10 smaller noodles; 20 smaller noodles for 8 servings).

Spread ½ cup marinara (1 cup for 8) in a 9-by-13-inch baking dish (for 8, divide sauce and roll-ups between two baking dishes).

Place one noodle on a work surface with a short side facing you; spread with 2 heaping TBSP filling, leaving a ½-inch border. Starting with a short side, gently roll up (don’t roll too tightly; filling might come out the sides!).

Place roll-up, seam side down, on top of marinara in baking dish. Repeat assembly with remaining noodles and filling.

Pour remaining marinara evenly over roll-ups, spreading to cover. Sprinkle with mozzarella.

Tightly cover baking dish with foil; bake on top rack for 20 minutes (for 8 servings, bake on top and middle racks).

Carefully remove foil. Return to top rack and bake until cheese begins to brown and noodles are tender, 5-8 minutes more.

Meanwhile, place baguette slices on a baking sheet. Top with a large drizzle of olive oil and season with salt and pepper. Bake on middle rack until lightly browned and toasted, 5-8 minutes (for 8 servings, you may need to toast the crostini after the roll-ups are done baking. Don’t worry, the roll-ups will stay hot!).

In a medium bowl, combine tomatoes, chives, lemon zest, and juice from remaining lemon wedges. Season with salt and pepper.

Top crostini with tomato mixture.

Serve lasagna roll-ups family style or divide between plates. Serve with tomato crostini on the side.