Set the oven to 425°F (218°C) and line a large sheet pan (17x12 or 18x13-inch) with parchment paper for easy cleanup.

Rinse the mushrooms briefly under running water and pat them dry. Slice cremini and button mushrooms into quarters, halve shiitakes, and tear oyster mushrooms into bite-sized pieces. Arrange the mushrooms in the center of the sheet pan and season with thyme, salt, and 2 tablespoons of olive oil. Toss gently with your hands until evenly coated.

Add the gnocchi and garlic cloves to the pan and toss again to combine. Distribute evenly across the pan. If using link sausage, slit the casings lengthwise and remove the meat. Break the sausage into small pieces (roughly the size of large marbles) and scatter them evenly over the pan.

Place the pan in the preheated oven and roast for 20 minutes. Remove from the oven, toss the ingredients gently with a spatula, and spread them evenly again. Return to the oven and continue roasting for an additional 10 minutes, or until the gnocchi are golden and slightly crisp, and the sausage is fully cooked.

While the gnocchi roasts, remove the softened garlic cloves from their skins and transfer them to a medium bowl. Mash the garlic with the back of a fork, then whisk in the lemon juice, water, and remaining 1 tablespoon of olive oil until smooth.

Add the chopped kale to the bowl with the dressing and toss to coat thoroughly. Spread the dressed kale evenly over the roasted gnocchi and sausage mixture on the sheet pan.

Return the pan to the oven and roast for an additional 10 minutes, or until the kale is tender and slightly crisp at the edges.

Transfer the gnocchi mixture to serving bowls. Drizzle with a touch of olive oil and sprinkle generously with freshly grated Parmesan cheese. Serve immediately.