Heat a large heavy-bottomed skillet over medium high heat and add the olive oil.
Add the shrimp, the garlic, cajun seasoning and salt and pepper and toss in the pan until everything is well coated. Let cook just until one side of the shrimp turns pink.
Flip the shrimp and add the white wine and lemon juice. Let the shrimp continue to cook just until they're completely pink and the wine has reduced to almost nothing.
Turn off the heat under the pan and let the shrimp stay in the warm pan until ready to serve.
For the polenta:
While the shrimp cooks, add the cornmeal, half and half, stock and salt to a large saucepan over medium high heat.
Stir the mixture together with a whisk as it heats up and comes to a boil.
Once it reaches a boil and thickens, remove it from the heat and add the parmesan.
Whisk in the parmesan just until it melts.
Serve the polenta in bowls (just under 1 cup of cooked polenta per serving) and top it with the shrimp and some freshly chopped parsley (optional).
Notes
The serving size for this recipe is just under 1 cup of cooked polenta and 1/4 of the cooked shrimp (the number of shrimp will vary, because shrimp vary in size).