Line two medium baking sheets with parchment and one extra, smaller baking sheet. Set aside.
Combine the minced rosemary, salt, pepper, lemon juice and oil in a bowl.
Slice the acorn squash and sweet potato about an inch thick across. Try to cut them so that you get a large cross section for stacking. After trimming the cauliflower, cut into cross sections to form steaks. Finally, thinly slice the apple.
Lay the slices on the baking sheets. Brush both sides with the rosemary oil mixture, and place baking sheet into the oven. The thicker vegetables should take about 40-45 minutes (or until tender with a fork) to brown up and soften, and the thinner vegetables and apples 10-15 minutes.
While the vegetables are roasting, cook the lentils according to the package, simmering about 25-30 minutes. Season lentils with salt and stir in a small amount of olive oil to keep them separated.
For the dressing, combine ingredients in a jar and mix until combined.
To serve, divide the warm lentils among plates, pressing down on them with the back of a spoon to make a flat surface. Stack the roasted vegetables on top of the flattened lentils from widest to narrowest and thinnest.
Drizzle the stacks with maple vinaigrette. Garnish with the nuts. Serve warm.