Preheat your oven to 400°F (200°C). On a baking sheet, toss the butternut squash cubes with 1 tablespoon of olive oil, brown sugar, cinnamon, cardamom, salt, and pepper. Roast for 15-20 minutes, or until the squash is tender and easily pierced with a fork.
While the squash roasts, arrange the baguette slices on another baking sheet. Brush them with 1 tablespoon of olive oil. Toast in the oven for 8-10 minutes, flipping halfway through, until golden and crisp. Set aside.
While the bread toasts, heat the remaining 1 tablespoon of olive oil in a skillet over medium-high heat. Remove the sausage from its casings and add it to the skillet. Cook, breaking it up with a spoon, until browned and cooked through. The internal temperature should reach 160°F (71°C).
Add the chopped kale to the skillet with the cooked sausage. Cook, stirring frequently, for 2-3 minutes until the kale has wilted. Remove from the heat and set aside.
Transfer the roasted squash to a food processor. Add the ricotta cheese and pulse until the mixture is smooth and creamy. Season with additional salt and pepper to your liking.
To assemble, spread a layer of the whipped butternut squash and ricotta mixture onto each toasted baguette slice. Top with a spoonful of the sausage and kale mixture. Serve immediately.